NEET 2014 Anatomy Past Paper PDF
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2014
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This is a NEET 2014 past paper covering human anatomy and physiology. The paper includes multiple choice questions on nerves, arteries, veins, and muscles of the upper limbs and lower limbs, along with concepts of the axilla. The questions range from basic to advanced, with explanations included for some of the answers.
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1. Anterior interosseous nerve is a branch of? a) Radial nerve b) Median nerve c) Ulnar nerve d) Axillary nerve Correct Answer - B Ans. is 'b' i.e., Median nerve Anterior interosseous nerve is a branch of median nerve. Anterior interosseous artery is a branch of ulnar artery. 2. Olecranon p...
1. Anterior interosseous nerve is a branch of? a) Radial nerve b) Median nerve c) Ulnar nerve d) Axillary nerve Correct Answer - B Ans. is 'b' i.e., Median nerve Anterior interosseous nerve is a branch of median nerve. Anterior interosseous artery is a branch of ulnar artery. 2. Olecranon process of ulna helps in formation of? a) Radial notch b) Trochlear notch c) Olecranon fossa d) Coronoid fossa. Correct Answer - B Ans. is 'b' i.e., Trochlear notch Inner surface of olecranon process forms trochlear notch for articulation of trochlea of humerus. Radial notch is seen in lateral part of upper end of shaft (not on olecronon). Olecranon fossa and coronoid fossa are part of lower end of humerus. 3. True about clavicle? a) Endochondral ossification b) Vertical c) No medullary cavity d) Rarely fractures Correct Answer - C Ans:C.)No medullary cavity. Peculiarities of Clavicle: 1.It has no medullary cavity 2. It is the first bone to ossify in the fetus (5th-6th week) 3. It is the only long bone having 2 primary centers of ossification (others have only 1) 4. It is the only long bone that ossifies in membrane and not in cartilage 5. It is the only long bone lying horizontally 6. It is the most common fractured long bone in the body 7. It is subcutaneous throughout 4. Clavipectoral fascia is pierced by all except ? a) Lateral pectoral nerve b) Median pectoral nerve c) Thoracoacromial vessels d) Cephalic vein Correct Answer - B Ans. is 'b' i.e., Median pectoral nerve Clavipectoral fascia is pierced by - Thoraco-Acromial vessels. Lateral pectoral nerve. Lymphatics passing from breast and pectoral region to apical-axillary 1.n. Cephalic vein. 5. Root value of supinator jerk - a) C3 C4 b) C4C5 c) C5 C6 d) C8 T1 Correct Answer - C C5 C6 6. Small muscles of hand are supplied by: a) C3 b) C4 c) C6 d) C5-7 , C-8 to T1 Correct Answer - D All small muscles of hand i.e. thener, hypothenar, interossei & lumbricals are supplied by median and ulnar nerves which originate from C5-7 and C8 and T1 nerves. 7. Bicipital aponeurosis lies over which structure in cubital fossa? a) Ulnar nerve b) Radial nerve c) Brachial artery d) Anterior interosseous artery Correct Answer - C Bicipital aponeurosis passes superficial to the brachial artery and median nerve. It lies deep to superficial veins. During venipuncture, the bicipital aponeurosis provides limited protection for brachial artery and median nerve. 8. Structure over bicipital aponeurosis in cubital fossa? a) Ulnar nerve b) Radial nerve c) Brachial artery d) Veins Correct Answer - D Veins 9. Nerve running along with profunda brachii artery, in spiral groove ? a) Ulnar b) Median c) Radial d) None Correct Answer - C Ans. is 'c' i.e., Radial Profunda brachii is a branch of brachial artery. It accompanies radial nerve in spiral groove. Branches of profunda brachii artery are :? 1. Deltoid branch (ascending branch) :- It anastomoses with the descending branch of posterior circumflex humeral artery. 2. Nutrient artery to humerus: 3. Muscular branches 4. Posterior descending (middle collateral) :- It anastomoses with interosseous recurrent branch of ulnar artery. 5. Anterior descending (radial collateral) :It anastomoses with radial recurrent branch of radial artery in front of lateral epicondyle. 10. Boundaries of quadrilateral space include all except? a) Teres major b) Long head of triceps c) Neck of humerus d) Deltoid Correct Answer - D Deltoid 11. Axillary artery is divided into three parts by? a) 1st rib b) Clavicle c) Pectoralis minor muscle d) Teres minor muscle Correct Answer - C Axillary artery It is the main artery of upper limb. It begins at the level of outer border of first rib as a continuation of subclavian artery. It ends at the level of lower border of teres major to continue as brachial artery. The axillary artery is covered anteriorly by pectoralis minor, which divides it into three parts:? 1) First part :- This part is proximal to upper border of pectoralis minor, i.e. extends from outer border of first rib to upper border of pectoralis minor. The branch of first part is Superior thoracic artery. 2) Second part :- This part is behind pectoral is minor. It gives following branches. A) Thoracoacromial artery :- It pierces clavipectoral foscia and gives following branches :- (i) Acromial (ii) Pectoral, (iii) Clavicular and deltoid. B) Lateral thoracic artery 3) Third part :- This part is distal to lower border of pectoralis minor, i.e. extends from pectoralis minor (lower border) to teres major (lower border). It gives following branches ? A) Subscapular artery:- It gives off circumflex scapular artery and then continues us thoracodorsal artery. B) Anterior circumflex humeral artery. C) Posterior circumflex humeral artery. Anterior and posterior circumflex arteries (both are branches of 3rd part of axillary artery) forms anastomosis around surgical neck of humerus. 12. Posterior wall of axilla is formed by a) Pectoralis major b) Pectoralis major c) Subscapularis d) Intercostal muscles Correct Answer - C Axilla (armpit) The axilla is apyramidal space situated between the upper part of the arm and the chest wall. It resembles afour sided pyramid, and has following : (i) an apex (ii) a base (iii) four walls (anterior, posterior, medial and lateral). 1. Anterior (pectoral) wall :- Formed by (i) Pectoralis major, (ii) Pectoralis minor, and (iii) Subclavius. The latter two muscles enclosed by clavipectoral fascia. 2. Posterior (subscapular) wall :- Formed by (i) Subcapularis, (ii) Teres major, and (iii) Latissimus dorsi. 3. Medial (thoracic) wall :- Formed by (i) Upper four ribs (with their intercostal muscles), and (ii) Upper part of serratus anterior. 4. Lateral (humeral) wall :- Formed by (i) Upper part of humerus with bicipital groove lodging the tendon of long head of biceps, and (ii) Corachobrachialis and short head of biceps ? 5. Base :- Formed by Skin, superficial fascia and deep (axillary) fascia. It is directed downwards. Apex :- It is directed upwards and medially towards the root of neck. It communicates with supraclavicular triangle of neck, hence referred to as Cervicoaxillary canal. It is triangular in shape and is bounded anteriorly by clavicle, posteriorly by upper part of scapula and medially by outer border of first rib. The axillary artery and brachial plaxus enter the axilla through this canal. plaxus enter the axilla through this canal. 13. Anterior axillary fold is due to which muscle ? a) Pectoralis major b) Pectoralis minor c) Subscapularis d) Teres major Correct Answer - A Anterior axillary fold is rounded in shaped and is formed by pectoralis major (lower border). Posterior axillary fold is formed by teres major and latisimus dorsi. 14. Intracapsular but extrasynovial is ? a) Long head of triceps b) Long head of biceps c) Short head of biceps d) Medial head of biceps Correct Answer - B Origin of long head of biceps is intracapsular but extrasynovial, enclosed by a prolongation of synovial membrane of shoulder joint. 15. How many lactiferous ducts open in nipple ? a) 0 -10 b) 15 -20 c) 25 -50 d) 50 -75 Correct Answer - B The nipple is pierced by 15-20 lectiferous ducts. 16. Structure related to deltopectoral groove ? a) Axillary artery b) Cephalic vein c) Baselic vein d) Radial nerve Correct Answer - B Ans. is b' i.e., Cephalic vein Deltopectoral groove is a groove between deltoid muscle and pectoralis major muscle. It is traversed by cephalic vein 17. Common interosseous artery is a branch of - a) Brachial artery b) Radial artery c) Ulnar artery d) Profunda branchii artery Correct Answer - C Branches of ulnar artery A) In cubital fossa 1) Anterior ulnar recurrent :- Anastomoses with inferior ulnar collateral in from of medial epicondyle. 2) Posterior ulnar recurrent :- Anastomoses with superior ulnar collateral behind medial cpicondyle. 3) Common interosseous :- Divides into i) Anterior interosseous : It is the deepest artery of front of forearm. It is accompanied by anterior interosseous nerve (a branch of median nerve). It pierces interosseous membrane at upper border of pronator quadratus to enter into extensor (dorsal) compartment. Its branches are : (a) muscular branches for deep muscles of front of forearm; (b) nutrient artery to radius and ulna; and (c) median artery. ii) Posterior interosseous : Near its origin, it gives of interosseous recurrent artery which ends by anastomosing with middle collateral artery. B) In forearm 1) Palmar carpal branch 2) Dorsal carpal branch C) In palm :- These are terminal branches. i) Deep branch :- Completes the deep palmar arch on medial side by joining the terminal part of radial artery. ii) Superficial branch :- Forms the major part of superficial palmar arch. 18. True about blood supply of scaphoid? a) Mainly through ulnar artery b) Major supply from ventral surface c) Major supply from dorsal surface d) Proximal supply in antegrade fashion Correct Answer - C Major blood supply (70-80%) of scaphoid comes through dorsal surface via dorsal branches of radial artery. These dorsal vessels enter the scaphoid at or just distal to waist area and supply the proximal pole in retrograde fashion. 19. 3rd and 4th lumbrical (lateral two lumbricals) of foot are supplied by ? a) Medial plantar nerve b) Lateral plantar nerve c) Peroneal nerve d) None of the above Correct Answer - B Behind the medial malleolus, beneath the flexor retinaculum the tibial nerve divides into its two terminal branches : i) Medial plantar nerve :- It corresponds approximately to the median nerve in the hand as far as skin and muscle supplies are concerned. It supplies medial part of sole, plantar surface of medial 3rd A digits, and innervates flexor digitorum brevis, abductor hallucis, flexor hallucis brevis and the first lumbrical. ii) Lateral plantar nerve :- It correspods approximately to the ulnar nerve. It supplies the lateral part of sole, plantar surface of lateral digits and innervates flexor digitorum accesorius, abductor digiti minimi, flexor digiti minimi brevis, adductor hallucis, all intcrossei and 2nd,3rd,4th lumbricals. 20. All are true about short saphenous vein except? a) Runs behind lateral malleolus b) Runs on lateral side of leg c) Accompanied by sural nerve d) Achillis tendon is medial to vein Correct Answer - B Short saphanous vein runs in the back (posteriorly) of leg (not laterally). It enters the back of leg by passing behind the lateral malleolus and is accompanied by sural nerve. In leg it ascends lateral to tendocalcaneous (tendoachillis). Thus tendoachillis is medial to vein. 21. Not true about inferior extensor retinaculum? a) Y shaped b) Superior slip attached to lower end of fibula c) Inferior slip attached to deep fascia of sole d) Lateral attached to calcaneum Correct Answer - B Ans. is 'b' i.e., Superior slip attached to the lower end of the fibula Inferior extensor retinaculum It is a Y-shaped band lying in front of the ankle joint. Attachments:- The stem of the inferior extensor retinaculum is attached to the upper surface of the calcaneus in front of sulcus calcanei. Passing medially, the stem divides into two bands. The upper band passes upwards and medially to be attached to tibial malleolus. The lower band extends downwards and medially to blend with plantar aponeurosis. Structures passing deep to it are : 1) Tibialis anterior tendon. 2) Extensor hallucis longus tendon. 3) Dorsalis pedis vessels. 4) The deep peroneal nerve. 5) Extensor digitorum longus tendons. 6) Peroneus Tertius tendon. 22. True about popliteus are all except? a) Flexor of knee b) Intracapsular origin c) Supplied by tibial nerve d) Causes locking of knee Correct Answer - D Popliteus Popliteus is a deep muscle of posterior compartment of leg. Features of popletius are - Origin Lateral surface of lateral condyle of femur, origin is intracapsular. Outer margin of lateral meniscus of knee. Insertion Posterior surface of shaft of tibia above soleal line. Nerve supply Tibial nerve Action Ulocks knee joint by lateral rotation of femur on tibia prior flexion. Accessory flexor of knee. 23. True regarding semitendinosus ? a) Supplied by common peroneal part of sciatic nerve b) Proximal flashy distal thin c) Distal flashy proximal thin d) Proximal and distal thin middle fleshy Correct Answer - D Semitendinosus is a fusiform (spinadle shaped) muscles with main mass in middle of it. It arises in thin tendon from ischial tuberosity and ends in a long tendon to insert on medial surface of proximal part of tibia. o It is supplied by tibial part of sciatic nerve. 24. Which of the following dorsiflexes the foot - a) Tibialis posterior b) Tibialis anterior c) Peroneus brevis d) Extensor digitorum brevis Correct Answer - B Tibialis anterior 25. Artery piercing the oblique popliteal ligament of knee - a) Superior genicular b) Inferior genicular c) Middle genicular d) Popliteal Correct Answer - C Middle genicular Oblique popliteal ligament is an expansion from the tendon of semimembranosus attachment to intercondylar line of femur. It is closely related to popliteal artery and is pierced by middle genicular vessels and nerve and the terminal part of the posterior division of the obturator nerve. 26. Lateral dislocation of patella is prevented by ? a) Rectus femoris b) Vastus intermedius c) Vastus lateralis d) Vastus medialis Correct Answer - D Vastus medialis 27. Hunter's canal is seen in? a) Cubital fossa b) Popliteal fossa c) Thigh d) Calf Correct Answer - C Ans. is 'c' i.e., Thigh 28. True about iliotibial tract all except? a) Receives insertion of gluteus maximus b) Derived from fascia lata c) Inserted on lateral tibial condyle d) None Correct Answer - D Iliotibial Tract The fascia lata is thickened laterally where it forms a 5 cm wide band called the iliotibial tract. Superiorly the tract splits into two laters. The superficial lamina is attached to tubercle of iliac crest, and deep lamina to the capsule of hip joint. Inferiorly, the tract is attached to a smooth area on anterior surface of the lateral condyle of tibia. The importance of the iliotibial tract is as follows. a) Two important muscles are inserted into its upper part, between the superficial and deep laminae. These are the three-fourths part of the gluteus maximus; and the tensor fasciae latae. b) The iliotibial tract stabilizes the knee both in extension and in partial flexion; and is, therefore, used constantly during walking and running. 29. Ligament supporting the talus is ? a) Spring ligament b) Deltoid ligament c) LCL d) Cervical ligament Correct Answer - A Ans. A) Spring ligament Spring ligament (Plantar calcaneonavicular ligament) connects the calcaneum with the navicular bone. However, its principal job is to provide a sling for the talus, to support the head of talus (though it has no attachment to talus). This aids in supporting the weight of the body. Weaknes or lengthening along this ligament can cause flat foot 30. False about tibia-fibula is ? a) Nutrient artery of tibia is from posterior tibial artery b) Nutrient artery of fibula is from peroneal artery c) Proximal end of tibia is related to common peroneal nerve d) Tibia is the most common site of osteomyelitis Correct Answer - C Common peroneal nerve is related to neck of fibula (not tibia). Nutrient artery of tibia is a branch of posterior tibial artery. Nutrient artery of fibula is a branch of peroneal artery. Tibia is the commonest site of osteomyelitis. 31. All are branches of lumbar plexus except? a) Iliohypogastric nerve b) Ilioinguinal nerve c) Obturator nerve d) Subcostal nerve Correct Answer - D Ans. is 'd' i.e., Subcostal nerve 32. Articular surface of the sarum extends upto how many vertebrae in males ? a) 1 to 11/2 b) 2 to 21/2 c) 3 to 31/2 d) 4 to 41/2 Correct Answer - C Articular surface of sacrum: the rough articular surface on the lateral aspects of the sacrum that articulates with the ilium on each side. 33. Lower limit of sacro iliac joint lies upto which level in females ? a) 1 to 1 1/2 b) 2 to 2 1/2 c) 3 to 3 1/2 d) 4 to 4 1/2 Correct Answer - B , 2 to 2 1/2 34. First rib is not related to ? a) Sympathetic chain b) Scalenus anterior c) Suprapleural membrane d) T2 Nerve Correct Answer - D Ans. is `d' i.e., T2 Nerve Anteriorly, the neck of the first rib is related to (from medial to lateral) :- (1) Sympathetic chain, (ii) Ist posterior intercostal vein, (iii) Supeior intercostal artery, and (iv) 1st thoracic nerve. These structures are between neck of first rib (posteriorly) and apex of lung (anteriorly). Following are attached to first rib :- Scalenus anterior, scalenus medius, subclavius, serratus anterior ( lst digitation), costo-clavicular ligament and suprapleural membrane. 35. True about anterior intercostal artery ? a) Present in 1st to 11th intercostal space b) Each intercostal space has two anterior intercostal arteries c) Branch of internal thoracic artery d) Branch of aorta Correct Answer - C Ans. is 'c' i.e., Branch of internal thoracic artery Each of upper nine intercostal spaces (1 to 9) have one posterior and two anterior intercostal arteries. The 10"and 11" spaces have one posterior intercostal artery (no anterior intercostal artery) Posterior intercostal artery is the main artery of intercostal space and runs in the costal groove along the upper border of an intercostal space, lying between posterior intercostal vein and intercostal nerve (relationship from above downward VAN). 1" and 2' posterior intercostal arteries are branches of superior intercostal artery (a branch of costocervical trunk from 2"d part of subclavian artery* 05)).Lower nine (3rd to 11`") posterior intercostal arteries are branches of descending thoracic aorta. Right posterior intercostal arteries are longer than the left. Anterior intercostal arteries for upper six spaces (two in each space) arise from internal thoracic or internal mammary artery. For 7th to 9th spaces, these are branches of musculophrenic artery (terminal branch of internal thoracic artery). 36. True about right principal bronchus ? a) Narrower b) Horizontal c) Shorter d) All are true Correct Answer - C Features of right bronchus (in comparison to left bronchus) 1) Shorter 2) Wider 3) Vertical (in the line of trachea). 37. Thoracic duct is formed by? a) Union of left subclavian and left internal jugular vein. b) Union of brachiocephalic vein and internal jugular vein c) Continuation of upper end of cisterna chyli d) None of the above Correct Answer - C Thoracic duct is also called as Pecquet duct. It is the largest lymphatic duct in body, about 45 cm (18 inches) long. It has a beaded appearance because of the presence of many valves in its lumen. Thoracic duct begins as a continuation of the upper end of the cisterna chyli near the lower border of T12 vertebra and enters the thorax through the aortic opening of diaphragm (at T12 ). It then ascends through the posterior mediastinum and at T5 level crosses from right side to the left side and ascends along left margin of oesophagus to enter the neck. At the level of C7 vertebrae, arches towards left side to open into left brachiocephalic vein at the angle of union of left subclavian and left internal jugular veins. 38. Thoracic duct opens into ? a) Subclavian vein b) Internal jugular vein c) Right brachiocephalic vein d) Left brachiocephalic vein Correct Answer - D Left brachiocephalic vein 39. Posterior relation of hilum of lung ? a) Azygous vein b) SVC c) Vagus nerve d) Arch of aorta Correct Answer - C Vagus nerve 40. Not related to hilum of right lung? a) Azygous vein b) Vagus nerve c) SVC d) Arch of aorta Correct Answer - D Arch of aorta is related to left lung. 41. Xiphoid fuses with sternum by what age ? a) 30 years b) 35 years c) 40 years d) 45 years Correct Answer - C Ans. is 'c' i.e., 40 years [Ref Parikh 6th le p. 2.30, 2.31] Sternum Pieces of body unite between 14-25 years. Xiphoid unites with body at 40 years. Manubrium unites with body at 60 years. Other bones Hyoid : greater cornu unites with body at 40-60 years. Laryngeal and costal cartilages ossify after 40 years. Vertebra : Osteophytes outgrowth, lipping of vertebra and disc atrophy occur. 42. Bronchopulmonary segments in right and left lungs respectively ? a) 9, 11 b) 11,9 c) 10,10 d) 8, 10 Correct Answer - C Each lung has 10 bronchopulmonary segments. 43. At the level of Arch of aorta, the relationship of left vagus nerve and left phrenic nerve? a) Phrenic nerve anterior, vagus nerve posterior b) Phrenic nerve posterior, vagus nerve anterior c) Both in same plane anteroposteriorly d) Variable in relationship Correct Answer - A Phrenic nerve anterior, vagus nerve posterior 44. Posterior to transverse pericardial sinus? a) Aorta b) Pulmonary trunk c) SVC d) Left atrium Correct Answer - C Ans. is 'c' i.e., SVC Transverse sinus is a short passage that lies between the reflection of serous pericardium (epicardium) around arterial (aorta and pulmonary trunk) and venous ends of the heart tube. Transverse sinus is bounded anteriorly by ascending aorta and pulmonary trunk, posteriorly by SVC, and inferiorly by left atrium. 45. True about cremasteric reflex? a) Afferent: genital branch of genitofemoral nerve b) Efferent: genital branch of genitofermoral nerve c) Efferent: femoral branch of genitofemoral nerve d) Afferent: pudendal nerve Correct Answer - B Ans. is 'b' i.e., Efferent : genital branch of genitofemoral nerve 46. Urethral crest is an elevation seen in urethra due to: a) Prostatic glands b) Insertion of detrusor muscle c) Insertion of trigone d) Preprostatic internal sphincter Correct Answer - A Answer- A (Prostatic glands) The urethral crest is an anatomical feature present in the urinary system of both males and females. The prostatic portion (pars prostatica), the widest and most dilatable part of the canal, is about 3 cm long. Upon the posterior wall or floor is a narrow longitudinal ridge, the urethral crest, formed by an elevation of the mucous membrane and its subjacent tissue. On either side of the crest is a slightly depressed fossa, the prostatic sinus, the floor of which is perforated by numerous apertures, the orifices of the prostatic ducts from the lateral lobes of the prostate; the ducts of the middle lobe open behind the crest. 47. Pyramidalis is supplied by ? a) Subcostal nerve b) Ilioinguinal nerve c) Iliohypogastric nerve d) Genitofemoral nerve Correct Answer - A Ans. is 'a' i.e., Subcostal nerve 48. Appendices epiploicae is a feature of ? a) Duodenum b) Stomach c) Colon d) Jejunum Correct Answer - C Characteristic features of large intestine i) 3 longitudinal bands, formed by longitudinal muscle coat, called Taeniae coli. ii) Sacculation or haustration iii) Fat filled peritoneal pouches called appendices epiploicae. These are not found in appendix, caecum, and rectum. iv) Greater part is fixed except for appendix, transverse colon and sigmoid colon. v) Pyere's patches (present in small intestine) are not present. 49. Appendices epiploicae is seen in all part of large intestine except - a) Sigmoid colon b) Ascending colon c) Caecum d) Transverse colon Correct Answer - C Ans. is 'c' i.e., Caecum Small bags of peritoneum filled with fat, called appendices epiploicae are present over the surface of large intestine, except for appendix, caecum and rectum. 50. Inferior rectal artery is a branch of? a) Inferior mesenteric artery b) Superior mesenteric artery c) Coeliac trunk d) Internal pudendal artery Correct Answer - D Ans. is 'd' i.e., Internal pudendal artery 51. Cremasteric artery is a branch of? a) Internal pudendal artery b) External pudendal artery c) Inferior epigastric artery d) Superior epigastric artery Correct Answer - C Inferior epigastric artery 52. Superficial epigastric artery is a branch of? a) Internal pudendal artery b) External pudendal artery c) Internal iliac artery d) Femoral artery Correct Answer - D Ans. is 'd' i.e., Femoral artery Branches of femoral artery 1) Superficial :- Superficial external pudendal, superficial epigastric, superficial circumflex iliac. 2) Deep branches :- Profunda femoris, deep external pudendal, muscular branches, descending genicular branch (last branch in the adductor canal). Note: Superior epigastric artery is a branch of internal thoracic artery. 53. Inferior epigastric vein drains into? a) Femoral vein b) External iliac vein c) Internal iliac vein d) Internal pudendal vein Correct Answer - B Ans. is 'b' i.e., External iliac vein Inferior epigastric vein drains into External iliac vein. Superior epigastic vein drains into Internal thoracic vein. 54. Superior rectal vein drains into? a) Inferior mesenteric vein b) External iliac vein c) Internal iliac vein d) Internal pudendal vein Correct Answer - A Ans. is 'a' i.e., Inferior mesenteric vein Superior rectal vein drains into inferior mesenteric vein. Inferior rectal vein drains into internal pudendal vein. 55. Most common location of accessory spleen? a) Hilum of spleen b) Greater omentum c) Lesser omentum d) None Correct Answer - A Accessory spleen may be found at :- i) Hilum of spleen (most common site). ii) Tail of pancrease. iii) Derivatives of dorsal mesogastrium :- Greater omentum, gastrophrenic ligament, gastrosplenic ligament, linorenal ligament. iv) Broad ligament of uterus (in males) and spermatic cord (in female); both left side. 56. Length of Posterior vaginal wall is a) Variable b) Same as anterior vaginal wall c) Less than anterior vaginal wall d) More than anterior vaginal wall Correct Answer - D Ans. is 'd' i.e., More than anterior vaginal wall Vagina The vagina is a fibromuscular, canal forming the female copulatory organ. It extends from vulva to uterus. Mucous membrane is lined by nonkeratinized stratified squamous epithelium. The anterior wall is about 8 cm long and the posterior wall is about 10 cm long. The lumen is circular at the upper end because of the protrusion of the cervix into it. Below the cervix, anterior and posterior walls are in contact. The interior of the upper end of the vagina (or vaginal vault) is in the form of a circular groove that surrounds the protrudng cervix. The groove becomes progressively deeper form before backwards and is arbitrarily divided into four parts called the vaginal fornices : Anterior fornix lies in front of the cervix and is shallowest. Posterior fornix lies behind the cervix and is deepest. Two lateral fornices lie one on each side of the cervix. Lateral fornix is related to the transverse cervical ligament of pelvic fascia in which are embedded a network of vaginal vein and the ureter gets crossed by the uterine artery. Relations of vagina Anterior wall Upper half is related to the base of the bladder. Lower half to the urethra. Posterior wall Upper one-fourth is separated from the rectum by the rectouterine pouch. Middle two-fourths are separated from the rectum by loose connective tissue. Lower one-fourths is separated from the anal canal by the perineal body and the muscles attached to it. Lateral walls One each side : Upper one-third is related to the transverse cervical ligament of pelvic fascia in which are embedded a network of vaginal veins, and the ureter gets crossed by the uterine artery. Middle one-third is related the pubococcygeus part of the levator ani. Lower one-third pierces the perineal membrane, below which it is related to the bulb of the vestibule, the bulbospongiosus and the duct of greater vestibular gland of bartholin. Arterial supply Vaginal branch of internal iliac (main supply) Cervicovaginal branch of uterine artery (in upper part). Middle rectal and internal pudendal arteries (in lower part). 57. Bare area of liver is related to - a) Aorta b) Hepatic vein c) Portal vein d) Gall bladder Correct Answer - B Hepatic vein Between two layers of coronary ligaments, there is a large triangular area in diaphragmatic surface of liver which is not covered by peritoneum. It is called 'bare area of liver'. It is related to inferior vena cava (IVC). The hepatic veins (usually three) leave the liver in bare area. This area is clinically important as it is a site where infection can spread from abdominal cavity to thoracic cavity. 58. True about circumcaval ureter ? a) Developmental anomaly of ureter b) Ureter passes in front of IVC from lateral to medial c) Mostly involves right ureter d) Type 2 is more common Correct Answer - C Circumcaval (retrocaval) ureter results from altered vasculature rather than ureteral development. Thus, preureteral vena-cava is more appropriate term. This disorder involves right ureter which passes behind IVC winding about and crosses in front of it from medial to lateral direction. The anomaly is divided into two types :? 1) Type 1 : It is more common and has hydronephrosis with a typically obstructing pattern demonstrating some degree of fish-hook shaped deformity of ureter. 2) Type 2 : It has lesser degree of hydronephrosis or not at all. 59. Which of the following is a retroperitoneal structure? a) Ileum b) Jejunum c) Ureter d) Appendix Correct Answer - C Ureter 60. Falciparum ligament contains? a) Ligamentum venosus b) Ligamentum teres c) Linorenal ligament d) None of the above Correct Answer - B Peritoneal ligaments 1. Gastrosplenic ligament :- It extends from hilum of spleen to greater curvature of stomach. It contains short gastric and left gastroepiploic vessels. 2. Linorenal ligament :- It extends from hilum of spleen to anterior surface of left kidney. It contains splenic vessels and tail of pancreas. It develops from dorsal mesogastrium. 3. Gastrophrenic ligament :- It connects the greater curvature of stomach to diaphragm. It develops from dorsal mesogastrium. 4. Phrenicocolic ligament :- It connects left colic (splenic) flexure to diaphragm. It supports the anterior border of spleen. 5. Falciform ligament :- It demarcates the right and left lobes of liver. It contains ligamentum teres (remnant of left umblical vein) and paraumblical vein. It develops of ventral mesogastrium (ventral part). 6. Coronary ligaments :- It contains superior and inferior layers which connect liver to diaphragm, and encloses the triangular 'bare area of liver'. 7. Triangular ligaments (a right and a left) :- These connect right and left lobes of liver to diaphragm. It develops from ventral mesogastrium. 61. Part of colon with no mesentery? a) Transverse colon b) Sigmoid colon c) Ascending colon d) Rectum Correct Answer - C Mesenteries in intestine 1) Mesentery proper :- Mesentery of small intestine (jejunum and ileum) is fan shaped double layered peritoneal fold which suspends the coils of jejunum and ileum. Mesentery has :? i) Attached border (root of mesentery) :- It is 15 cm long and extends from duodenojejunal flexure (on left side of L2) to upper part of right sacroiliac joint. Root of mesentery crosses following structures :- (i) 3rd part (horizontal part) of duodenum, (ii) abdominal aorta, (iii) IVC, (iv) right ureter, and (v) right psoas major. ii) Free border (intestinal border) :- It is 6 meters long and is attached to gut forming its visceral peritoneum (serous coat). 2) Transverse mesocolon :- It connects transverse colon to posterior abdominal wall and contains middle colic vessels. 3) Mesoappendix :- It connects the appendix to the ileal mesentery and contains appendicular vessels. 4) Sigmoid mesocolon :- It connects sigmoid colon to posterior pelvic wall and contains sigmoid vessels. 5) Mesorectum : It contains superior rectal vessels (artery & veins) with their branches, lymphatic vessels and lymph nodes along with their branches, lymphatic vessels and lymph nodes along superior rectal artery, and branches from inferior mesenteric plexus. 62. False regarding trigone of bladder ? a) Lined by transitional epithelium b) Mucosa smooth and firmly adherent. c) Internal urethral orifice lies at lateral angle of base d) Developed from mesonephric duct Correct Answer - C Trigone of bladder has following features : 1) Lined by transitional epithelium 2) Mucosa is smooth and firmly adherent 3) Ureters open at lateral angles of base and internal urethral orifice lies at apex. 4) Has Trigonal muscle of bell (smooth muscle layer just beneath mucosa). 5) Derived from absorbed part of mesonephric duct (Wolffian duct). 63. Trigone of urinary bladder develops from: a) Mesoderm b) Ectoderm c) Endoderm of urachus d) None of the above Correct Answer - A With differential growth of the dorsal bladder wall, the ureters come to open through the lateral angles of the bladder, and the mesonephric ducts open close together in what will be the urethra. That part of the dorsal bladder wall marked off by the openings of these four ducts forms the trigone of the bladder. Thus, lining of the bladder over the trigone is mesodermal in origin; The smooth muscle of the bladder wall is derived from the splanchnopleuric mesoderm. The apex of the bladder is continuous with the allantois, which now becomes obliterated and forms a fibrous core, the urachus. The urachus persists throughout life as a ligament that runs from the apex of the bladder to the umbilicus and is called the median umbilical ligament o Linining epithelium of bladder mucosa is transitional epithelium. When empty mucosa is thrown into rugae except in trigone, where mucosa is smooth and firmly adherent. o just beneath the mucosa of trigone there is layer of smooth muscle, Trtgonal muscle of Bell which replaces the submucous coat in trigone area 64. Watershed zone of large intestine ? a) Cecum b) Ascending colon c) Rectosigmoid d) Transverse colon Correct Answer - C There are areas of colon with poor blood supply resulting from incomplete anastomosis of marginal arteries. These are watershed areas of colon and include : 1. Splenic flexure (Griffith point) : Watershed area between superior mesenteric artery and inferior mesenteric artery. 2. Rectosigmoid junction (Sudeck's point) : Watershed zone between inferior mesenteric artery and internal iliac artery. 65. Ligament extending from cervix and vagina to lateral pelvic wall ? a) Broad ligament b) Pubocervical ligament c) Round ligament d) Transverse cervical ligament Correct Answer - D Transverse cervical ligaments of Mackenrodt are fan-shaped condensation of endopelvic fascia on each side of cervix above the levator ani and around uterine vessels. They connect lateral aspect of cervix and upper vaginal wall to lateral pelvic wall. They form a 'hammock' that supports the uterus. 66. True about Scarpa's fascia ? a) Deep fascia of anterior abdominal wall b) Also called Buck's fascia c) Attached to Iliotibial tract d) Forms suspensory ligament of penis Correct Answer - D Fascia of anterior abdominal wall A) Superficial fascia The superficial fascia of anterior abdominal wall (below the level of umblicus) is divided into : Superficial fatty layer (fascia of camper or camper's fascia), and deep membraneus layer (fascia of scarpa or scarpa's fascia). The fatty layer (fascia of camper) is continuous with the superficial fascia of adjoining part of the body. However, in the penis it is devoid of fat and in scrotum it is replaced by dartos muscle, i.e., in scrotum dartos muscle is present instead of fatty layer of superficial fascia. B) Deep fascia It is present in the form of a thin layer covering the muscles and their aponeuroses and large neurovascular structures. At superficial inguinal ring it continues over the spermatic cord as external spermatic fascia into scrotum and continue over the penis as deep fascia of penis (Buck's fascia). 67. Where is the Cave of Retzius present? a) Between urinary bladder and rectum b) Between urinary bladder and cervix c) In front of the bladder d) Between the cervix and the rectum Correct Answer - C Space of Retzius is a horse-shoe shaped potential space which intervenes between the antero-lateral pelvic wall and the sides of the bladder and prostate. 68. Nerve entering the inguinal canal through deep inguinal ring ? a) Ilioinguinal nerve b) Pudendal nerve c) Genital branch of genitofemoral d) Superior rectal nerve Correct Answer - C The spermatic cord in males and round ligament of uterus in females, enter the inguinal canal through the deep inguinal ring and pass out through superficial inguinal ring. Thus consituents of spermatic cord are also components of inguinal canal; these are ductus deferens (vas deferens), testicular artery, cremestric artery, artery to ductus deference, pampiniform plexus, lymphatics, sympathetic plexus, genital branch of genitofemoral nerve, remains of process vaginalis. Note: Ili oiguinal nerve enters inguinal canal through interval between external and internal oblique muscles (not through deep inguinal ring). 69. Initially, renal arteries are branches of ? a) Internal pudendal artery b) External iliac artery c) Common iliac artery d) Aorta Correct Answer - C Due to ascent of kidneys during development, the blood supply of kidney changes:? 1) Initially when the kidneys are in pelvis, the renal arteries are branches of common iliac arteries. 2) With progressive ascent, the arteries to kidneys are derived from different levels of aorta. 70. In a neonate, kidney is supplied by? a) Internal pudendal artery b) External iliac artery c) Common iliac artery d) Aorta Correct Answer - D Upto 5th week of intrauterine life, kidney is in lumbar region and renal arteries are branches of common iliac artery (see above explanation). After that, differential growth of abdominal wall causes the kidney to ascent to lumbar region. Adult position (lumbar region of abdomen) is attained by 9th week. Druing progressive ascent, the arteries to kidney are derived from different levels of aorta. After full ascent, definitive renal artery is branch of aorta at 2nd lumbar segment. Thus, neonatal kidney is supplied by aorta. 71. External oblique forms all except? a) Lacunar ligament b) Pectineal ligament c) Conjoint tendon d) Inguinal ligament Correct Answer - C Inguinal ligament (Poupart's ligament) is the folded lower border of external oblique aponeurosis Lacunar ligament (Gimbernats ligament) is the crescent shaped expansion from the medial end of inguinal ligament attached to pectineal line of pubis. Pectineal ligament (Cooper's ligament) is strong fibrous band extending laterally from the lacunar ligament along pectineal line of pubis. Similar to lacunar ligament, it is made of external oblique aponeurosis. Reflected part of inguinal ligament extends from the lateral crus of superficial inguinal ring formed by inguinal ligament upwards to linea alba. It forms the posterior wall of inguinal canal. Conjoint tendon (falx inguinalis) is formed by the aponeuroses of internal oblique and transversus abdominis muscle and is attached to pubic crest. 72. Meckel's cave is related to ? a) Submandibular ganglion b) Trigeminal ganglion c) Otic ganglion d) Pterygopalatine ganglion Correct Answer - B Ans. is 'b' i.e., Trigeminal ganglion Trigeminal ganglion (Gasserion ganglion or semilunar ganglion) lies in a dural pouch, the cavum trigeminale (Meckel's cave). 73. Longest spinous process is seen in ? a) C2 b) C4 c) C5 d) C7 Correct Answer - D Ans. is 'd' i.e., C7 Cervical Vertebrae There are 7 cervical vertebrae of which 3-6 are typical and 1st, 2nd and 7th are atypical. Characteristic features of typical cervical vertebra are : - i. Foramen transversarium is present in the transverse process. Foramina transversaria of Cl to C6 vertebrae transmit vertebral artery, vertebral vein and sympathetic plexus, and that of C7 transmits only vertebral veins. ii. Body is small and broad transversely (side to side). iii. Spinous process is small and bifid. iv. Vertebral foramen is large and triangular. v. Superior articular facet is directed backwards and upwards, and inferior facet is directed downwards and forwards. Articular process are placed horizontally, So that dislocation can occur without fracture. vi. The anterior tubercle on transverse process of C6 vertebra is prominent and is called carotid tubercle or chaissagnac's tubercle. It is related to common carotid artery which can be palpated against it. Erb's point is opposite chassaignac's tubercle. Cricoid cartilage is at same level (C6 vertebra). Important features of atypical vertebrae are : ? 1. First cervical vertebra (atlas) is ring like bone having lateral mass on each side connected by a smaller anterior arch and a larger posterior arch. Anterior arch has a facet for dens of axis. Each lateral mass has an upper articular facet for occipital condyle and lower facet for body of C2 (axis) vertebra. Cl vertebra does not have body and spinous process. 2. Second cervical vertebra (axis) is characterized by presence of odontoid process or dens, a peg-like projection from the body. 3. Seventh cervical vertebra is called as vertebra prominens because it has most promenent spinous process which is not bifid. Foramen transversarium transmits only vertebral vein, not vertebral artery. 74. Sweat gland near the lid margins a) Moll b) Zeis c) Meibomian d) Krause Correct Answer - A Ans. is 'a' i.e., Moll Glands of Moll (Moll's gland) are apocrine sweat glands just next to the eyelashes. Zeis glands are sebaceous glands near lid margins. Meibomian gland (tarsal glands) are specialized sebaceous gland at the rim of eyelids inside the tarsal plate. Krause's glands are accessory lacrimal glands underneath the eyelid. 75. Anterior lymphatics from the nose drain into ? a) Pretracheal nodes b) Submandibular nodes c) Sublingual nodes d) Superficial cervical nodes Correct Answer - B Ans. is 'b' i.e., Submandibular nodes Submandibular nodes These nodes lie deep to investing layer of deep cervical fascia in submandibular triangle, between the deep fascia and submandibular gland. These nodes receive afferents from centre of forehead; anterior part of nasal cavity; frontal, maxillary and ethmoidal air sinuses; inner canthus (medial angle of eye); whole of upper lip and anterior part of cheek with underlying gum and teeth; outer part of lower lip with lower gums and teeth excluding incisors; anterior two third of tongue excluding the tip; floor of mouth; and angle of mouth. These nodes also receives efferents of submental nodes. Submandibular nodes drain into (efferent) upper and lower deep cervical nodes. 76. Killian's dehisence is seen in ? a) Oropharynx b) Nasopharynx c) Cricopharynx d) Vocal cords Correct Answer - C Ans. is 'c' i.e., Cricopharynx Inferior constrictor muscle has two parts :- (i) Thyropharyngeous with oblique fibres, and (ii) Cricopharyngeous with transverse fibres. Between these two parts of inferior constrictor exists a potential gap called Killan's dehiscence. It is also called the gateway to tear as perforation can occur at this site during esophagoscopy. It is also the site for herniation of pharyngeal mucosa in case of pharyngeal pouch. 77. Fossa incudis is related to ? a) Head of malleus b) Long process of incus c) Short process of incus d) Foot process of stapes Correct Answer - C Fossa incudis contains short process of Incus. Head of malleus is attached to epitympanum by ligament of head of malleus. Long process of incus is attached to head of stapes. Footplate of stapes lies over oval window. 78. Unpaired laryngeal cartilage ? a) Arytenoid b) Corniculate c) Cuneiform d) Epiglottis Correct Answer - D The skeletal supports of larynx is provided by Six cartilages, 3 out of which are paired (so there are total 9 cartilages). i) Unpaired :- Thyroid, cricoid, epiglottis. ii) Paired :- Arytenoid, Corniculate, cuneiform. 79. Which is the only nerve which exits the brainstem on dorsal side ? a) Facial b) Trigeminal c) Trochlear d) Abducent Correct Answer - C Unique features of trochlear nerve are :? i) Most selender cranial nerve. ii) Only cranial nerve to emerge on the dorsal aspect of brain. iii) Only cranial nerve to undergo complete internal decussation before emerging i.e. right trochlear nerve arises from left trochlear nucleus and vice versa. iv) Has'longest intracranial course (Vagus nerve has overall longest course). v) Thinnest cranial nerve (smallest nerve in terms of the number of axons it contains). 80. Blood supply of putamen includes all except? a) Medial striate arteries b) Lateral striate arteries c) Anterior choroidal artery d) Posterior communicating artery Correct Answer - D Blood supply of basal ganglia Caudate nucleus and putamen are supplied by lateral and medial striate branches of anterior, medial and posterior cerebral arteries. Putamen receives additional supply from anterior choroidal artery. o Globus pallidus is supplied by lateral striate and anterior choroidal arteries. 81. Medulla is supplied by all except? a) Basilar artery b) Anterior spinal artery c) Vertebral artery d) Posterior cerebral artery Correct Answer - D Posterior cerebral artery 82. Length of Eustachian tube? a) 12 mm b) 24mm c) 36mm d) 48mm Correct Answer - C Length of Eustachian tube is 36 mm. (reached by the age of 7 years) Lateral third (i.e. 12 mm) is bony. Medial 2/3 (i.e. 24 mm) is fibrocartilaginous. 83. Parasympathetic supply to lacrimal glands are passed through ? a) Lesser petorsal nerve b) Chorda tympani c) Greater petorsal nerve d) Lingual nerve Correct Answer - C Greater petorsal nerve 84. Onodi cells are seen in? a) Sphenoid sinus b) Maxillary sinus c) Anterior ethmoidal sinus d) Posterior ethmoidal sinus Correct Answer - D Ethmoidal sinuses are divided into two groups : A) Anterior group i) Anterior ethmoidal air cells Anterior ethmoidal air cells drain into- either the ethmoidal infundibulum or the frontonasal duct. Some air cells may invade the orbital floor. These are known as the Haller' cells. ii) Middle ethmoidal air cells Also known as bullar sinuses. The middle ethmoidal air cells drain- into the middle meatus by one or more orifices on or above the ethmoidal bulla. B) Posterior group Posterior ethmoidal air cells usually drain- into the superior meatus. The posterior group lies very close to the optic canal and optic nerve. The Onodi cell is usually regarded as the most posterior ethmoid cell that pneumatizes lateral and superior to the sphenoid sinus and is intimately associated with the optic nerve. 85. Haller cells are seen in? a) Roof of nose b) Orbital floor c) Lateral nasal wall d) Maxillary sinus Correct Answer - B The Onodi and Haller cells are ethmoidal air cells. Some air cells may invade the orbital floor. These are known as the Haller' cells. The Onodi cell is usually regarded as the most posterior ethmoid cell that pneumatizes lateral and superior to the sphenoid sinus and is intimately associated with the optic nerve. 86. Which valve is present at opening of nasolacrimal duct? a) Hasner's valve b) Heister valve c) Spiral valve d) None Correct Answer - A Nasolacrimal duct opens into inferior meatus and is closed by a mucosal flap called Hasner's valve. Heister valve (spiral valve) is present in cyctic duct. 87. Cribriform plate forms ? a) Roof of olfactory region b) Floor of olfactory region c) Nasal septum d) All of the above Correct Answer - A Internal nose Internal nose has following parts i) Nasal cavity proper :- Internal nose is divided into right and left nasal cavities by nasal septum. Each nasal cavity communicates with the exterior through naris or nostrils and with nasopharynx through posterior nasal aperture or posterior ?tares or choana. ii) Vestibule of nose :- Anterior and inferior part of the nasal cavity is lined by skin and is called vestibule of nose. It contains sebaceous glands, hair follicles and the hair called vibrissae. Each nasal cavity has a lateral wall, a medial wall (nasal septum), a roof, and a floor. The olfactory mucosa lines upper 1/3 of nasal cavity including the roof formed by cribriform plate, and medial and lateral wall up to the level of superior concha. 88. Galen's anastomosis is between ? a) Recurrent laryngeal nerve and external laryngeal nerve b) Recurrent laryngeal nerve and internal laryngeal nerve c) Internal laryngeal nerve and external laryngeal nerve d) None of the above Correct Answer - B Ans. is 'b' i.e., Recurrent laryngeal nerve and internal laryngeal nerve There are two types of important anastmosis between laryngeal branches of vagus :? 1. Galen anastomosis (Ramus anastomoticus or Ansa of Galen) This is an anastomosis between the recurrent laryngeal nerve and internal laryngeal nerve (internal branch of superior laryngeal nerve). Generally, posterior branch of recurrent laryngeal nerve contributes to the anastomosis; however, anterior branch can also contribute. 2. Human communicating nerve It is an anastomosis between recurrent laryngeal nerve (distal part) and external laryngeal nerve (external branch of superior laryngeal nerve). 89. Lamina papyracea is between ? a) Optic nerve and orbit b) Maxillary sinus and orbit c) Ethmoid sinus and orbit d) Cranial cavity and orbit Correct Answer - C The thinnest portion of medial wall of orbit is the lamina papyracea which separates ethmoid sinuses from orbit. o Infection from ethmoidal sinus can easily breach this paper thin bone and affect the orbital contents. 90. False about sternocleidomastoid? a) Arises from sternum and clavicle b) Insertes on mastoid process c) Motor supply by spinal accessory nerve d) Tilt the head on opposite side Correct Answer - D Sternocleidomastoid tsternomastoidl Origin 1. The, sternal head 2. The clavicular head Insertion It is inserted : 1. By a thick tendon into the lateral surface of mastoid process, from its tip to superior border. 2. By a thin apponeurosis into the lateral half of the superior nuchal line of the occipital bone. Nerve supply 3. The spinal accessory nerve provides the motor supply. It passes through the muscle. 4. Branches from the ventral rami of C2 are proprioceptive. Blood supply Arterial supply-one branch each from superior thyroid artery and suprascapular artery and, two branches from the occipital artery supply the big muscle. Veins follow the arteries. Actions 1. When one muscle contracts : a) It turns the chin to the opposite side. b) It can also tilt the head towards the shoulder of same side. 2. When both muscles contract together : 2. When both muscles contract together : a) They draw the head forwards, as in eating and in lifting the head from a pillow. b) With the longus colli, they flex the neck against resistance. c) It also helps in forced inspiration. 91. The key to the root of the neck is the scalenus anterior muscle. Which among the following is TRUE about scalenus anterior? a) Not Pierced by phrenic nerve b) Attached to scalene tubercle on 2nd rib c) Separates subclavian artery from subclavian vein d) Pierced by phrenic nerve Correct Answer - A Ans. (A) Not pierced by phrenic nerve The subclavian vein forms an arch across the pleura at a level below the arch of subclavian artery. The two arches are separated from each other by scalenus anterior muscle. Scalenus anterior arises from the anterior tubercles of C3-C6 and attaches to the scalene tubercle and adjacent ridge on the inner border and upper surface of the first rib. Phrenic nerve passes vertically down across the obliquity of the muscle, plastered there to by the prevertebral fascia. Transcervical and suprascapular arteries lie between the scalenus anterior and the carotid sheath. 92. Tongue muscle which is not developed from occipital myotome ? a) Styloglossus b) Hyoglossus c) Genioglossus d) Palatoglossus Correct Answer - D DEVELOPMENT OF THE TONGUE :? I. Epithelium a) Ant 2/3 -- lingual swellings of 1st arch and tuberculum impar b) Post 1/3 -- large dorsal part of hypobranchial eminence, Le. 3rd arch c) Posterior most part -- small dorsal part of the hypobranchial eminence, i.e. 4th arch II. Muscles From occipital myotomes except palatoglossus which is derived from the 6th arch. 93. Korner's septum is seen in ? a) Petrosquamous suture b) Temporosquamous suture c) Petromastoid suture d) Frontozygomatic suture Correct Answer - A Mastoid develops from squamous and petrous bone. Korner's septum is persistence of petrosquamous suture in the form of a bony plate. Korner's septum is surgically important as it may cause difficulty in locating the antrum and the deeper (ells, and thus lead to incomplete removal of disease at mastoidectomy. Mastoid antrum cannot be reached unless the Korners septum has been removed. 94. What is true about chorda tympani? a) Postganglionic sympathetic b) Preganglionic sympathetic c) Preganglionic parasympathetic d) Postgalglionic parasympathetic Correct Answer - C Chorda tympani arises from intratemporal part (in fallopion canal) of facial nerve. * It carries preganglionic secretomotor fibers (not postganglionic) to submandibular and sublingual glands. * It joins lingual nerve in infratemporal fossa. * It carries taste sensations from anterior 2/3 of tongue. 95. Vidian nerve is formed by union of? a) Superficial petrosal nerve and deep petrosal nerve b) Greater petrosal nerve and superficial petrosal nerve c) Greater petrosal nerve and deep petrosal nerve d) Greater petrosal nerve and external petrosal nerve Correct Answer - C Greater petorsal nerve units with deep petrosal nerve to form nerve to pterygoid canal (also called vidian nerve). 96. Woodruff's area is located at ? a) Antero-inferior part of nasal septum b) Posteroinferior part of nasal septum c) Superior part of nasal septum d) Posteroinferior part of lateral nasal wall Correct Answer - D Posteriorly on the lateral nasal wall is the area known as Woodruff's area. It is situated under the posterior end of inferior turbinate. Sphenopalatine artery anastomoses with posterior pharyngeal artery, in this area. 97. Scutum is present in middle ear ? a) Roof b) Lateral wall c) Medial wall d) Floor Correct Answer - B Lateral wall 98. Not a part of bony labyrinth? a) Cochlea b) Vestibule c) Utricle d) Semicircular canal Correct Answer - C The inner ear within the petrous part of temporal bone consists of a membranous labyrinth enclosed in a bony (osseous) labyrinth. So, inner ear has two parts : ? Bony labyrinth :- Cochlea, Vestibule, Semicircular canals. Membranous labyrinth :- Cochlear duct, utricle, Saccules, three semicircular ducts, and endolymphatic duct & sac. 99. Lymphatic drainage of thyroid gland is mainly ? a) Sublingual nodes b) Submandibular nodes c) Deep cervical nodes d) Submental nodes Correct Answer - C Lymphatic drainage of thyroid Lymph from the upper part of the gland reaches the upper deep cervical lymph nodes either directly or through the prelaryngeal nodes. Lymph from the lower part of the gland drains to the lower deep cervical nodes directly, and also through the pretracheal and paratracheal nodes. 100. Organ of corti is situated in ? a) Basilar membrane b) Utricle c) Saccule d) None of the above Correct Answer - A Scala media (cochlear duct or membranous labyrinth) has 3 walls : - The basilar membrane, which supports the organ of corti. The Reissner's membrane which separates it from the scala vestibuli. The stria vascularis which contains vascular epithelium and is concerned with secretion of endolymph. 101. Floor of 4th ventricle has ? a) Infundibulum b) Vagal triangle c) Mammillary body d) Tuber cincrium Correct Answer - B Floor of 4th ventricle (Rhomboid fossa) It is diamond or rhomboidal shaped and is formed by posterior surface of pons (upper triangular part or pontine part) and dorsal surface of medulla (lower triangular part or medullary part) junction of pons and medulla forms intermediate part. Features of 4th ventricle are :? i. Median sulcus (a midline groove) divides the floor into two symmetrical halves. ii. Medial eminence is present an each side of median sulcus. It presents facial colliculus formed by genu (recurving fibers) of facial nerve looping around abducent nucleus. Facial colliculus lies in pons (i.e. in pontine part of floor). iii. Hypoglossal triangle overlying hypoglossal nucleus and vagal triangle overlying dorsal nucleus of vagus. Both of these triangle lie in the medulla (medullary part of floor). iv. Vestibular area overlies vestibular nuclei, partly in pons and partly in medulla. v. Sulcus coeruleus, a bluish area due to presence of pigmented neurons containing substantia ferruginea. vi. Superior and inferior favea. 102. Middle meningeal artery passes through ? a) Foramen ovale b) Foramen lacerum c) Foramen rotundum d) Foramen spinosum Correct Answer - D Foramen spinosum 103. Nerve which loops around submandibular duct? a) Mandibular nerve b) Lingual nerve c) Hypoglossal nerve d) Recurrent laryngeal nerve Correct Answer - B Submandibular duct It is 5 cm long duct and runs forwards on hyoglossus, between lingual and hypoglossal nerves. At the anterior border of the hyoglossus muscle it is crossed by lingual nerve which loops around it. It opens into the floor of mouth, on the summit of the sublingual papilla at the side of frenulum of tongue. 104. Medulla oblongata is derived from ? a) Telencephalon b) Diencephalon c) Mesencephalon d) Myelencephalon Correct Answer - D Ans. is d i.e., Myelencephalon Nervous system develops from ectoderm (neuroectoderm). Nervous system develops from neural tube which in turn develops by process of neurulation, i.e. formation of neural plate and its infolding into neural tube. Structures formed from neural tube are :? A) From cranial part (enlarged cephalic part) Gives rise to brain. Developmental parts are : i) Forebrain (prosencephalon) Telencephalon : Cerebral hemisphere and lateral ventricle. Diencephalon : Optic cup and stalk (gives rise to retina), pituitary, thalamus, hypothalamus, epithalamus, pineal gland, and third ventricle. ii) Midbrain (mesencephalon) Cerebral aqueduct. iii) Hindbrain (rhombencephalon) Metencephalon : Cerebellum, pons Myelencephalon Medulla oblongata B) From caudal part Gives rise to spinal cord. 105. Morula is how many celled - a) 4 b) 8 c) 12 d) 16 Correct Answer - D Ans. is 'd' i.e., 16 At about 16 cells stage the blastomeres tightly align by the process of compaction to form a compact ball of cells called morula (mulberry). This process of compaction leads to segregation of cells into two groups : 1. Inner cells (inner cell mass) 2. Outer cells (outer cell mass) Morula enters uterine cavity 4 days after fertilization. 106. Dental papilla give rise to ? a) Enamel b) Dental cuticle c) Tooth pulp d) None Correct Answer - C Repeat from previous sessions. See explanation-5 of session-1 107. Malleus and incus are derived from ? a) 1st Arch b) 2nd Arch c) 3rd Arch d) 4th Arch Correct Answer - A Ans. is 'a' i.e., 1st Arch lst (mandibular arch):- Muscular Contribution:-Muscles of mastication, Anterior belly of the digastric, Mylohyoid, Tensor tympani, Tensor veli palatini. Skeletal Contributions:- Maxilla, mandible (only as a model for mandible ), Incus and malleus, Meckel's cartilage, Ant. ligament of malleus, Sphenomandibular ligament. Nerve:- Trigeminal nerve (V2 and V3). Artery:- Maxillary artery, external carotid artery. 108. Optic cup is derived from ? a) Neural ectoderm b) Surface ectoderm c) Mesoderm d) Neural crest Correct Answer - A Ans. is 'a' i.e., Neural ectoderm 109. Optic cup give rise to ? a) Lens b) Retina c) Cornea d) Sclera Correct Answer - B Retina 110. Excretory system of kidney is derived from ? a) Ureteric bud b) Mesonephros c) Metanephros d) None Correct Answer - C Ans. is 'c' i.e., Metanephros Development of kidney Ureteric bud (mesonephros) arise from mesonephric duct and gives rise to collecting system of kidney (renal pelvis, major and minor calyces, collecting tubule) and ureter. Metanephric mesoderm (blastema or metanephors) arise from nephrogenic cord which in turn is derived from intermediate mesoderm. It gives rise to excretory unit (nephron), i.e. glomeruli, PCT, Loop of henle and DCT. 111. Ureteric bud arises from ? a) Paramesonephric Dut b) Mullerian duct c) Mesonephric duct d) Mesonephric tubule Correct Answer - C Genital duct system During 5th and 6th weeks, both male and females have two genital duct systems, deriverd from mesoderm : 1. Mesonephric duct (wolffian duct) and mesonephric tubules. 2. Paramesonephric duct (Mullerian duct). Mesonephric duct is the main genital duct in males as it gives rise to mainly male genital system : 112. Derivative of vitelline vein? a) IVC b) SVC c) Ligamentum venosum d) Ligamentum teres Correct Answer - A Ans. is 'a' i.e., IVC 113. Not true about development of ovary ? a) Develops in genital ridge b) Sex cords are derived from coelomic epithelium c) Oocytes are mesodermal in origin d) At birth ovary contains 2 million follicles Correct Answer - C Development of ovary Coelomic epithelium on medial side of the mesonephros becomes thickened to form genital ridge, the site where ovary develops. Genital ridge is covered by germinal epithelium (previous coelomic epithelium). From these germinal epithelium, cords of cells (sex cords or medullary cords) proliferate and grow into the underlying mesoderm. Primordial germ cells which are developed from endodermal cells of hindgut (part of yolk sac), migrate to region of developing ovary (genital ridge area) and give rise to oocytes. The sex cords become broken up into small masses. The cells of each mass surround one oocyte to form primordial follicle. At birth each ovary contains about 2 million primary follicles. 114. Testis lies at deep inguinal ring upto ? a) 4 months b) 5 months c) 7 months d) 9 months Correct Answer - C The testes develop in relation to the lumbar region of the posterior abdominal wall. During fetal life, they gradually descend to the scrotum. They reach the iliac fossa during third month, and lie at the site of deep inguinal ring upto 7 month of intrauterine life. They pass through inguinal canal during seven month, and are normally in the scrotum by the end of eighth month. 115. Position of testis at 24-28 weeks of intrauterine life? a) Inguinal canal b) Lumbar region c) Superficial inguinal ring d) Deep inguinal ring Correct Answer - D Deep inguinal ring 116. True about notochord are all except? a) Defines axis of embryo b) Serves as primary inductor c) Derived from hypoblast d) Remains as nucleus pulposus Correct Answer - C Notochord is a bud like structure formed by epiblast cells extending from cranial end of primitive streak to caudal end of prochordal plate, in between the ectoderm and endoderm. Siginificances of notochord includes following :- i. It defines the axis of embryo. ii. It functions as the primary inductor, inducing the overlying ectoderm to develop into neural plate (the primordium of CNS). iii. It serves as the basis for development of axial skeleton. The notochord is an intricate structure around which vertebral column is formed and indicates future site of vertebral bodies. However, the notochord does not give rise to vertebral column, after development of vertebral bodies, the notochord degenerates and disappears, but parts of it persist as the nucleus pulposus of intervertebral disc. 117. Remnant of notochord is ? a) Annulus fibrosus b) Nucleus pulposus c) Ligament flavum d) Intertransverse ligament Correct Answer - B Ans. is 'b' i.e., Nucleus pulposus Notochord is a bud like structure formed by epihlast cells extending from cranial end of primitive streak to caudal endof prochordal plate, in between the ectoderm and endoderm. Siginificances of notochord includes following :- It defines the axis of embryo. It functions as the primary inductor, inducing the overlying ectoderm to develop into neural plate (the primordium of CNS). It serves as the basis for development of axial skeleton. The notochord is an intricate structure around which vertebral column is formed and indicates future site of vertebral bodies. However, the notochord does not give rise to vertebral column, after development of vertebral bodies, the notochord degenerates and disappears, but parts of it persist as the nucleus pulposus of intervertebral disc. 118. 2ndpart of duodenum is derived from ? a) Foregut b) Midgut c) Both foregut & midgut d) Hindgut Correct Answer - C Both foregut & midgut 119. Stroma of cornea develops from ? a) Neural ectoderm b) Surface ectoderm c) Mesoderm d) Neural crest Correct Answer - C Corneal epithelium develops from Surface ectoderm. Corneal stroma develops from Mesoderm. 120. Female genital tract develops from ? a) Mesonephric duct b) Mesonephric tubules c) Mullerian duct d) None Correct Answer - C Mesonephric duct (Wolffian duct) is the main genital duct in males as it gives rise to mainly male genital system. Paramesonephric duct (Mullerian duct) gives rise to mainly female genital tract 121. Glomus cells are derived from ? a) Surface ectoderm b) Neuroectoderm c) Mesoderm d) Endoderm Correct Answer - B Glomus cells are derived from neural crest which itself is derivative of neuroectoderm. Other derivates of neural crest are? a) Neural derivatives Sensory neurons of spinal dorsal root ganglia. Sympathetic chain ganglia and plexus (celiac/preaortic/renal ganglia, enteric plexus in GIT, i.e. Auerbachs and Meissner's) Parasympathetic ganglia and plexus of GIT. Schwann cells of peripheral nerves, satellite cells of all ganglia. Adrenal medulla, chromaffin cells, para follicular C-cells of thyroid gland. Melanocytes and melanoblasts. b) Mesenchymal derivatives Dermal bones of skull : Frontal, parietal, temporal, nasal, vomer, palatine, mandible, maxillae. Leptomeninges : arachnoid and pia mater (Durameter is mesodermal). Dentine of teeth (odontoblasts). Eye : choroid, sclera, iris epithelium, pupillary muscles (sphincter and dilator pupillae, ciliary muscles). Pharyngeal arch cartilages. Retinal pigmented epithelium. Connective tissues of head including dermis, tendon, ligaments. Bulbar and conal ridges of heart. 122. Epithelium of vagina arises from? a) Ectoderm b) Wolffian duct c) Mesoderm d) Mesonephric duct Correct Answer - C Vagina is derived from two sources :- 1. Upper 2/3rd : It is derived from Utero-Vaginal Canal, i.e. the fused part of paramesonephric duct. Therefore, this part is mesodermal in origin. 2. Lower 1/3rd : It is derived from sinovaginal bulb which inturn is derived from urogenital sinus. Thus, this part is endodermal in origin. 123. Which of the following is derived from Ist arch? a) Frontonasal process b) Maxillary process c) Mandibular process d) Both maxillary & mandibular processes Correct Answer - D Face is developed from five facial primordia appear as prominences of mesenchyme:? 1. One frontonasal process : Begins as a proliferation of mesenchyme on ventral surface of developing brain. 2. Two maxillary processes : Grow out from the upper end of each first arch. 3. Two mandibular processes : Grow from each first arch. 124. Skeletal derivative of Ist arch ? a) Stapes b) Hyoid c) Maxilla d) Laryngeal cortilages Correct Answer - C Maxilla 125. Styloid process is derived from ? a) 1st arch b) 2nd arch c) 3rd arch d) 4th arch Correct Answer - B Styloid process is derived from 2nd pharyngeal arch. 126. Pharyngeal muscles are derived from which pharyngeal arch ? a) 1st b) 2nd c) 3rd d) 5th Correct Answer - C 3rd 127. Secondary ossification center for lower end of femur? a) Present at birth b) Appears at 6 months of age c) Appears at 1 year of age d) Appears at 5 years of age Correct Answer - A Secondary center of lower end of femur appears at 9th month of intrauterine life (present at birth). Ossification of femur The femur ossifies from one primary and four secondary centres. The primary centre for the shaft appears in the seventh week of intrauterine life. The secondary centres appear, one for the lower end at the end of the ninth month of intrauterine life, one for the head during the first six months of life, one for the greater trochanter during the fourth year, and one for the lesser trochanter during the twelfth year. There are three epiphyses at the upper end and one epiphysis at the lower end. The upper epiphyses; lesser trochanter, greater trochanter and head, in that order, fuse with the shaft at about eighteen years. The lower epiphysis fuses by the twentieth year. 128. Sternochondral joint is ? a) Primary cartilaginous b) Secondary cartilaginous c) Fibrous d) Synovial Correct Answer - A Ans. is 'a' i.e., Primary cartilaginous Costochondral (sternochondral) joints are primary cartilaginous joints. Cartilaginous joints 1) Primary cartilaginous joints (synchondrosis, or hyaline cartilage joint) : These are :- i. Joint between epiphysis and diaphysis of a growing long bone, i.e. physis. ii. Spheno-occipital joint iii. 1st costosternal joint (1st chondrosternal joint) iv. Costochondral joints 2) Secondary cartilaginous joints (Symphyses or fibrocartilaginous joints) : These are :- i. Symphysis pubis ii. manubriosternal joint iii. Symphysis menti iv. Sacroccygeal joint v. intervertebral disc 129. Innervated structures of joints are all except ? a) Synovium b) Capsule c) Articular cartilage d) Ligaments Correct Answer - C Ans. is 'c' i.e., Articular cartilage Characteristic features of articular cartilage 1) Hyaline cartilage 2) No innervation (no nerve supply). 3) No blood supply (avascular). 4) No lymphatics 5) Only hyaline cartilage which has no perichondrium. 6) No ability to repair or regenerate itself. 130. Submucosal plexus is ? a) Myenteric plexus b) Auerbach's plexus c) Meissner's plexus d) Tympanic plexus Correct Answer - C Innervation of GIT The gastrointestinal tract has a nervous system all its own called the enteric nervous system. It lies entirely in the wall of the gut, begining in the esophagus and extending all the way to the anus. The enteric nervous system is composed mainly of two plexus : - i) Myenteric plexus orAuerbach's plexus ii) Meissner's plexus or submucosal plexus Extrinsic nerves (Parasympathetic and sympathetic) are connected to both myenteric and submucosal plexuses. Enteric nervous system can function independently of these extrinsic nerves and these extrinsic nerves only modify the activity of the enteric nervous system. Therefore, peristalsis is present even if the intestine is deprived of extrinsic innervation. Parasympathetic stimulation enhances GI motility and secretion where as sympathetic stimulation inhibits motility and secretions. 131. Hassall's corpuscles are found in? a) Lymph nodes b) Spleen c) Liver d) Thymus Correct Answer - D The dominant feature of medulla of thymus is its epithelial components, which are onion like structures called Hassall's Corpuscles, which have an intensely eosinophilic core of dead material, 132. Duct of Bellini are present in: a) Pancreas b) Liver c) Kidney d) Salivary gland Correct Answer - C Answer C. Kidney Papillary (collecting) ducts are anatomical structures of the kidneys, previously known as the ducts of Bellini. Papillary ducts represent the most distal portion of the collecting duct. They receive renal filtrate (precursor to urine) from several medullary collecting ducts and empty into a minor calyx. 133. Breast is a ? a) Endocrine gland b) Modified sweat gland c) Modified sehaceous gland d) Holocrine gland Correct Answer - B Breast is a modified sweat gland. It is apocrine type of sweat gland. 134. Valve of heister is seen in a) Cystic duct b) Common bile duct c) Common hepatic duct d) Pancreatic duct Correct Answer - A Ans. is 'a' i.e., Cystic duct The mucous membrane of the cystic duct forms a series of 5-12 crescentic folds, arranged spirally to form the so called spiral valve of Heister. This is not a true valve. Also know Hartmanns pouch - dilated posteromedial wall of neck of gall bladder. Sphincter choledochus - always present - terminal part of bile duct Sphincter pancreaticus - usually present - terminal part of pancreatic duct Sphincter ampullae (of Oddi) - surrounds the hepatopancreatic ampulla 135. Skin over hypothenar eminence is supplied by? a) Radial nerve b) Median nerve c) Anterior interosseous nerve d) Ulnar nerve Correct Answer - D Ulnar nerve 136. Which of the following are inactive during normal respiration ? a) Pre-Botzinger complex b) Dorsal group of neurons c) Ventral VRG group of neurons d) Pneumotaxic center Correct Answer - C Ans. is 'c' i.e., Ventral group of neurons Medullary respiratory centers The principal areas in the medulla oblongata concerned with regulation of respiration are : ? 1) Dorsal respiratory group (DRG) : - The dorsal respiratory group of neurons are mainly concerned with inspiration. They descend and terminate on spinal motor neurons innervating the primary muscles of inspiration, i.e., the diaphragm and the external intercostal muscles. 2) Ventral respiratory group (VRG) : - The ventral respiratory group of neurons is mainly concerned with forceful expiration but also shows some activity during inspiration. Therefore, these neurons contribute to both expiration and inspiration. These neurons are divided into : ? i) The rostral VRG neurons : - These neurons show activity primarily synchronous with inspiration and therefore be called inspiratory (I) neurons. They terminate on spinal motor neurons supplying the accessory muscles of inspiration, i.e., sternocleidomastoid, scalenes and anterior serrati. ii) The ventral VRG neurons : - These are mostly expiratory (E) neurons. But since the expiration is generally a passive process, E neurons are silent most of the time. However, these neurons show activity when expiration is forceful, as during exercise. These neurons terminate on spinal motor neurons supply the muscles of expiration, i.e., internal intercostal and abdominal muscles. 3) Pre-Botzinger complex : - These neurons are responsible for generation of respiratory rhythm, i.e., the pacemaker cells which regulate the rate of respiration are located in Pre-Botzinger complex. Pontine respiratory centers The important pontine areas concerned with respiration are : ? 1) Pneumotoxic center (nucleus parabrachialis medialis) : - It is located in upper part of pons and transmits signals to the inspiratory area. The function of the pneumotaxic center is primarily to limit inspiration, i.e., the primary effect of this center is to control the "switch-off" point of the inspiratory ramp thus controlling the depth of inspiration, i.e., the duration of the filling phase of the lung cycle. Pneumotaxic center also inhibits apneustic center further inhibiting inspiration. Therefore strong stimulation of this center results in an early termination of inspiratory ramp and hence, inspiration is shortened and the tidal volume decreases. Conversely, in the absence of inputs from this center, inspiratory ramp continues much longer and hence inspiration is prolonged and the tidal volume increases. 2) Apneustic center : - This center located in the lower (caudal) part of pons. The apneustic center excites inspiratory center (DRG) and produce a prolonged inspiratory drive which delays the onset of expiration. Thus, though the respiratory rhythm is established in the medulla, this rhythm is spoilt by a strong inspiratory drive orginating in the apneustic centers. However, two influences seems to keep the apneustic center in check : (i) Pneumotaxic center of upper pons and (ii) Influence from stretch receptors in lung via vagus. Both of these influence inhibit inspiratory activity. 137. What will occur with increase in alveolar ventilation rate ? a) Decreased partial pressure of O2 in alveoli b) Decreased partial pressure of CO2 in alveoli c) Decreased CO2 diffusion from blood to alveoli d) Decreased O2 diffusion from alveoli to blood Correct Answer - B Ans. is 'b' i.e., Decreased partial pressure of CO2 in alveoli Alveolar ventilation is the amount of inspired air entering in gas- exchange areas (alveoli) per minute during quite breathing. It excludes the air which remains in dead space. 138. Pulmonary vasodilatation is caused by ? a) Hypoxia b) Thromboxane A2 c) Histamine d) Angiotensin-II Correct Answer - C Ans. is 'c' i.e., Histamine 139. Isocapnic exercise is ? a) Breathing for short duration against resistance b) Breathing of decreased volume of ventilation c) Breathing of increased volume of ventilation for long period d) Breathing of decreased volume for long period Correct Answer - C Ans. is 'c' i.e., Breathing of increased volume of ventilation for long period 140. Mismatch of ventilation/perfusion ratio is seen in a) Apex b) Base c) Both d) None Correct Answer - C Ans. is 'C' i.e.,Both Ventilation perfusion ratio (V/O) o Considering that cardiac output is 5.0 L/min and alveolar ventilation is about 4.2 L/min, the overall ventilation: perfusion ratio is 0-8. Idealy, therefore, each alveolus should have a V/Q ratio of 0.8. However, that is not so even in normal lungs. o Due to gravity, the apical alveoli are both underventilated and underperfused while the basal alveoli are both overventilated and overperfused. However, gravity affects perfusion much more than it affects ventilation. Hence, apical alveoli are more underperfused than underventilated while the basal alveoli are more overperfused than overventilated. Therefore, V/Q is maximun at apex (about 3-0) and least at base (about 0-6). o Since ventilation is far in excess of perfusion at apex, comparatively little oxygen is transferred from the alveoli to the blood, and CO2 transferred to the alveoli is also less. Hence the gas tension at the apices are quiet close to those of inspired air, i.e., High Pa02 and low PaCO2. On the other hand, at the base of lung perfusion is better than ventilation; Hence Pa02 and PaCO2 of basal alveoli are quiet close to those of pulmonary artery, i.e., low PaO, and high PaCO2. In simple words, ventilation-perfusion mismatch is responsible for high P02 with low PCO2 at apex and Low PO2 with high PCO2 at base. 141. Plateau of oxygen-hemoglobin dissociation curve signifies ? a) No oxygen is available for binding to Hb b) No Hb molecule is available to bind with O2 c) All oxygen is released to tissues d) None of the above Correct Answer - B Ans. is 'b' i.e., No Hb molecule is available to bind with O2 Each molecule of hemoglobin can combine with upto four molecules of oxygen. Combination with the first molecule alters the conformation of the hemoglobin molecule in such a way as to facilitate combination with the next oxygen molecule. In light of this, if we look at the curve, as the PO2 starts rising from 0 mm Hg upwards, initially all hemoglobin molecules in blood starts combining with their first oxygen molecule. This is the most difficult molecule to combine with. Hence saturation rises only slowly with initial rise in PO2. As PO2 rises further, hemoglobin molecules combine with their second, third and fourth molecules, which are progressively easier to combine with. Hence saturation rises steeply between PO2 of 15 mm Hg and 40 mm Hg. When PO2 rises still further, oxygen finds most of the hemoglobin molecules carrying four molecules of oxygen each. Since no molecules of hemoglobin can carry more than four molecules of oxygen, there is not much scope for more O2 combining with hemoglobin. Hence the curve becomes almost flat again beyond the PO2 of 60 mm Hg. 142. The oxygen dissociation curve of myoglobin & hemoglobin is different due to? a) Hb can bind to 2 oxygen molecules b) Cooperative binding in Hb c) Myogloobin has little oxygen affinity d) Hemoglobin follows a hyperbolic curve Correct Answer - B Ans. is `b' i.e., Cooperative binding in Hb Cooperative binding is responsible for sigmoid shape of the oxygen- hemoglobin dissociation curve. As myoglobin is monomeric (consists of one polypeptide chain only), it can bind only one molecule of oxygen and for the same reason myoglobin cannot show the phenomenon of cooperative binding. Hence, the oxygen?myoglobin dissociation curve is hyperbola as compared to sigmoid shape of Hb-O2 curve. Hemoglobin - O2 binding Each molecule of hemoglobin can combine with upto four molecules of oxygen. Combination with the first molecule alters the conformation of the hemoglobin molecule in such a way as to facilitate combination with the next oxygen molecule. In light of this, if we look at the curve, as the PO2 starts rising from 0 mm Hg upwards, initially all hemoglobin molecules in blood starts combining with their first oxygen molecule. This is the most difficult molecule to combine with. Hence saturation rises only slowly with initial rise in PO2. As PO2 rises further, hemoglobin molecules combine with their second, third and fourth molecules, which are progressively easier to combine with. Hence saturation rises steeply between PO2 of 15 mm Hg and 40 mm Hg. When PO2 rises still further, oxygen finds most of the hemoglobin molecules carrying four molecules of oxygen each. Since no molecules of hemoglobin can carry more than four molecules of oxygen, there is not much scope for more O2 combining with hemoglobin. Hence the curve becomes almost flat again beyond the PO2 of 60 mm Hg. Thus, the primary reason for the sigmoid shape of the oxygen- hemoglobin dissociation curve is that out of the four molecules of oxygen that can combine with a hemoglobin molecules, the first combines with the greatest difficulty and binding of an oxygen molecules increases affinity to next O2 molecule. This phenomenon is termed as cooperative binding or cooperativity, i.e., a molecule of O2 binds to a hemoglobin tetramer more readily if other O2 molecules are already bound. Myoglobin O2 binding Myoglobin is present in higher concentration in red (slow) muscle fibers. Myoglobin has greater affinity for oxygen than hemoglobin and its P50 is only 5 mm Hg (as compared to PO2 of hemoglobin which is about 26 mm Hg). Therefore, myoglobin-oxygen dissociation curve is shifted far to the left than Hb-O2 dissociation curve. It has shape of hyperbola as compared to sigmoid shape of Hb-O2 curve because it binds 1 molecule of O2 per mole (in comparison to Hb which binds 4 molecules of O2 per mole). The role of myoglobin is to bind O2 at very low PO2 and release them at even lower PO2, for example in exercising muscles where PO2 close to zero. 143. Compensatory mechanism in acute hemorrhage? a) Decreased myocardial contractility b) Decreased heart rate c) Increased heart rate d) Increased respiratory rate Correct Answer - C Ans. is 'c' i.e., Increased heart rate Compensatory mechanisms in acute hemorrhage In acute hemorrhage there is compensatory sympathetic stimulation which causes :? 1) Generalized vasoconstriction with increased total peripheral resistance (TFR). 2) Increased heart rate (tachycardia). 3) Increased cardiac contractility. 4) Increased renin release causing sodium and water retention through RAA system. 5) Shift of fluid from intracellular and interstitial space into vascular space. 144. 'v' Wave in JVP is due to ? a) Right atrial contraction b) Left atrial contraction c) Right atrial relaxation d) Closure of tricuspid valve Correct Answer - A Ans. is A The first elevation (a wave) corresponds to the slight rise in atrial pressure resulting from atrial contraction. The first descent (x descent) reflects a fall in atrial pressure that starts with atrial relaxation. The second elevation (v wave) corresponds to ventricular systole when blood is entering the right atrium from the vena cavae while the tricuspid valve is closed. Finally, the second descent (y descent) reflects falling right atrial pressure as the tricuspid valve opens and blood drains from the atrium into the ventricle. 145. Blood supply of brain is ? a) 1500 ml/min b) 2000 ml/min c) 750 ml/min d) 250 ml/min Correct Answer - C Ans. is 'c' i.e., 750 ml/min The cerebral blood flow (CBF) is about 750 ml/min (15% of total cardiac output), or 54 ml/100 gm brain tissue per minute. 146. Major neurotransmitter in afferents in nucleus tractus solitarius to regulate cardiovascular system ? a) Serotoxin b) Glutamate c) Glycine d) Norepinephrine Correct Answer - B Ans. is 'b' i.e., Glutamate Nucleus tractus solitarius (NTS) lies in medulla. It receives following afferents :? A) General visceral afferents i) From tonsil, pharynx, posterior part of tongue, carotid body and sinus → through glossopharyngeal nerve. ii) From pharynx, larynx, trachea, esophagus, and other thoracic and abdominal viscera → through vagus nerve. B) Special visceral afferents i) From anterior 2/3 of tongue (except circumvallate papillae) and palate → through facial nerve ii) From posterior 1/3 of tongue (including circumvallate papillae) → through glossopharyngeal nerve. iii) From posterior most part of tongue and epiglottis → through vagus nerve. NTS is involved in regulation of cardiovascular system through baroreceptors and chemoreceptors. There is a general consensus that glutamate is the neurotransmitter released at the therminals of baroreceptor and chemoreceptor afferents in NTS. — www.springer.com However, cholinergic, GABAergic, and opioidergic mechanisms are also present in NTS. 147. Dicrotic notch is caused by a) Closure of mitral valve b) Opening of mitral valve c) Closure of aortic valve d) Opening of aortic valve Correct Answer - C Ans. is 'c' i.e.. Closure of aortic valve Aortic pressure curve With the onset of the rapid ejection phase of the ventricular systole, the aortic pressure rises steeply to reach a maximum of about 120 mm Hg. The ejection of blood into the aorta causes a stretch on the aortic walls and makes the blood in the entire arterial system to move at a faster rate. This sets up a pressure wave that travels along the arteries. The pressure wave expands the arterial wall as it travels, and expansion is palpable as the pulse. In the later part of the ventricular systole, the aortic pressure declines and continues to decline throughout the diastole, to reach a minimum of about 80 mm Hg during the isometric contraction of the next cardiac cycle. The elastic recoil of the aorta and the resistance of arterioles help to maintain relatively high aortic pressure during diastole. A notch (incisura or dicrotic notch) is recorded in the early part of the downstroke of the aortic pressure curve. It corresponds to the closure of the aortic valve. It is produced by the sudden backward flow of aortic blood followed by the immediate cessation of backflow due to closure of the aortic valves. 148. Skin blood flow is decreased by ? a) Dopamine b) Isoprenaline c) Noradrenaline d) Acetylcholine Correct Answer - C Ans. is 'c' i.e., Noradrenaline Autophagy is the process by which cells sequester and degrade their own cytoplasmic organelles. During the process, autophagic vacuole is formed, which is a bilayer vacule containing unnecessary or dysfunctional organelle. Autophagic vacule fuses with lysosome to form autophagosome (autophagolysosome). Then, hydrolytic enzymes of lysosome degrade the organelle of autophagic vacuole. 149. S2 is associated with ? a) Rapid ventricular filling b) Atrial contraction c) Closure of semilunar valves d) Closure of AV valves Correct Answer - C Ans. C. Closure of semilunar valves S2 is due to closure of semilunar valves (aortic and pulmonary valves). 150. Capacitance vessels have in their wall ? a) More elastic tissue and less muscle b) Less elastic tissue and more muscle c) More elastic tissue and more muscle d) Less elastic tissue and less muscle Correct Answer - D Ans. is 'd' i.e., Less elastic tissue and less muscle Veins are capacitance vessels. They have less smooth muscle and less elastic tissue in their wall. Structure of vessels A) Structure of artery It is made up three layers - 1.Tunica Intima The inner most layer (towards lumen) of artery is intima. It consists of endothelial cells which rest on basment membrane. There is some subendothelial connective tissue. Intima is separated from media by internal elastic lamina. 2.Tunica Media It is mainly contains smooth muscles and laminae of elastic tissue Media is separated from adventitia by external elastic lamina. 3.Tunica Adventitia It is the outer most layer. Contains collegen and elastic fibers. B) Structure of capillaries Capillaries are thin walled vessels made up of single layer of endothelial cells with its basement membrane. o Capillaries are of three types - 1.Continous capillaries - These capillaries has continuous lining of endothelial cells with no These capillaries has continuous lining of endothelial cells with no fenestration. Basement membrane is also continuous. 2.Fenesterated capillaries There are fenestration between the endothelial cells. Basment membrane is continuous. 3.Sinusoidal capillaries Both endothelial cells and basement membrane have fenestration. In resting tissues, most of the capillaries are collapsed and blood flows through the throughfare vessels from the arterioles to the venules. C) Structure of veins Structure of vein is smiliar to artery except that - 1.Wall is thinner 2.Three tunicae are less well demarcated. 3.Elastic tissue is scanty and not clearly organized into distinct internal and external elastic lamina. 4.Have valves (except venae cavae and common iliac vein). 151. In circulatory biomechanics which of the following is true? a) Blood viscosity is increased in anemia b) Blood viscosity is decreased in polycythemia c) Cardiac output is increased in anemia d) Cardiac output is decreased in Beri-Beri Correct Answer - C Ans. is 'c' i.e., Cardiac output is increased in anemia Cardiac output is increased in conditions which cause decrease in peripheral vascular resistance :- Exercise 1. AV fistula or shunt 2. Severe anemia 3. Thyrotoxicosis 4. Wet beri-beri 5. About other options Blood viscosity is low in anemia and high in polycythemia. 152. Normal capillar wedge pressure ? a) 0-2 mm Hg b) 5-10 mm Hg c) 15-20 mm Hg d) 20-30mm Hg Correct Answer - B Ans. is 'b' i.e., 5-10 mm Hg Normal capillary Wedge pressure is 4-12mm Hg. It is a measure of left atrial pressure. 153. Mannitol infusion causes increase in a) Blood viscosity b) Osmolarity c) Intra-ocular tension d) Intercranial tension Correct Answer - B Ans. is 'b' i.e., Omolarity 154. Correct order of velocity ? a) Vena cava > Aorta > Vein > Artery > Venule > Arteriole b) Aorta > Vena cava > Artery > Vein > Arteriole > Venule c) Aorta > Artery > Vena cava > Vein > Arteriole > Venule d) Vena cava > Vein > Aorta > Artery > Venule > Arteriole Correct Answer - B Ans. is `b' i.e., Aorta > Vena cava > Artery > Vein > Arteriole > Venul 155. Effect of infusion of hypotonic saline? a) Increased ICF only b) Increased ECF only c) Increased in both ICF and ECF d) Increased ICF and decreased ECF Correct Answer - C Ans. is 'c' i.e., Increased in both ICF and ECF After infusion of hyptonic saline causes a decline in plasma osmolality and a shift of water into interstial space (as water moves from higher osmolarity to lower osmolarity), causing decrease in ICF osmolality. This results in shift of water from ECF to ICF. Finally, both ECF and ICF compartments are increased (due to increases water) and osmolality of both compartment are decreased. 156. Normal QRS axis ? a) +30 to 110° b) -30 to +110° c) +110° to +150° d) -110° to -150° Correct Answer - B Ans. is 'b' i.e., -30 to +110° In a normal heart, the average direction of the vector during spread of the depolarization wave through the ventricles, called the mean QRS vector, is about +59 degrees. This means that during most of the depolarization wave, the apex of the heart remains positive with respect to the base of the heart. The normal electrical axis of the heart (mean electrical axis or mean QRS vector) lies between -30° and + 100°. If the axis is more negative than -30° it is called left axis deviation, whereas if the axis is more positive than + 100°, it is called right axis deviation. 157. Herring Breuer reflex is an increase in ? a) Duration of inspiration b) Duration of expiration c) Depth of inspiration d) Depth of expiration Correct Answer - B Ans. is 'b' i.e., Duration of expiration The Hering-Breuer inflation reflex is an increase in the duration of expiration produced by steady lung inflation, and the Hering-Breuer deflation reflex is a decrease in the duration of expiration produced by marked deflation of the lung. 158. Carotid and aortic bodies are stimulated when ? a) Oxygen saturation decreases below 90% b) Oxygen saturation decreases below 80% c) Oxygen saturation decreases below 70% d) Oxygen saturation decreases below 60% Correct Answer - A Ans. is 'a' i.e., Oxygen saturation decreases below 90% Peripheral chemoreceptors (carotid and aortic bodies) are stimulated if arterial PO2 is below 60 mmHg. At PO2 of 60 mmHg, O2 saturation is about 90% (89%). 159. Baroreceptor are ? a) Carotid body b) Carotid sinus c) Aortic body d) None Correct Answer - B Ans. is 'b' i.e., Carotid sinus Baroreceptors are mechanoreceptors that are located in the adventia of carotid artery and aorta, at specialized locations called sinuses. 1) Carotid sinus is a little bulge at the root of internal carotid artery, located just above the bifurcation of the common carotid artery. It is innervated by the sinus nerve, a branch of glossopharyngeal (IX cranial) nerve. 2) Aortic arch (aortic sinus) also contains mechenoreceptors (stretch receptors) which are similar to carotid sinus receptors. However, their afferent nerve fibers travel in the aortic nerve, a branch of Vagus (X cranial) nerve. The sinus nerve (from carotid sinus) and aortic nerve/vagal fibers (from aortic sinus) are together called `Sinoaortic nerves'. They, together, are also refered to as 'Buffer nerves' because they are the afferents of cardiovascular reflexes that buffer abrupt changes in blood pressure. 160. Sleep centre is located in - a) Basal ganglia b) Medulla c) Hypothalamus d) Cerebellum Correct Answer - C Ans. is 'c' i.e., Hypothalamus 161. Umami taste is evoked by ? a) Glucose b) Glutamic acid c) Quinine d) Sodium chloride Correct Answer - B Ans. is 'b' i.e., Glutamic acid There are four basic tastes namely Sweet, bitter Salty and Sour. There mechanisms of sensory transduction are : 1) Sweet receptor is a G protein coupled receptor and leads to an increase in cAMP concentration in the sensory cells which results in closure of K+ channels and depolarization. 2) Bitter receptors are also G protein coupled receptors and causes rise in intracellular Ca' by IP3-DAG system. Rise in intracellular Ca+2 triggers neurotransmitter release. 3) Salty-tasting substances depolarize taste cells by activating amiloride-sensitive Na+ channels. 4) Sour-tasting substances depolarize taste cells by raising the intracellular H + ion concentration, which causes closure of K+ channels. The umami taste is the fifth taste which is unique. The proposed mechanism of umami taste is through glutamate taste sensors (glutamate receptors) with release of neuronal glutamic acid. In nature, there are three umami substances :- i) Monosodium glutamate (MSG) ii) Disodium 51-guanosine mosphosphate (GMP) iii) Disodium 51-ionsine monophosphate (IMP) 162. Reward center is located in ? a) Cerebellum b) Amygdala c) Hippocampus d) Hypothalamus Correct Answer - D Ans. is 'd' i.e., Hypothalamus 163. Which is not an extrapyramidal tract ? a) Reticulospinal tract b) Rubrospinal tract c) Corticospinal tract d) Tectospinal tract Correct Answer - C Ans. is 'c' i.e., Corticospinal tract 164. While walking or standing, posture is maintain by ? a) Basal ganglia b) Hypothalamus c) Cerebellum d) Amygdala Correct Answer - C Ans. is 'c' i.e., Cerebellum Cerebellum, through its connection with the red nucleus influences the activity of brainstem reticular formation and thereby gamma motor neuron activity. Through its connections with the vestibular nucleus and vestibulospinal tract, cerebellum influnences the activity of alpha motor neurons. Thus, normal cerebellar function is essential for the maintenance of normal muscle tone and posture. The cerebellum seems to play crucial roles in walking as well as maintaing a standing posture. Cerebellar vermis plays an important role in maintenance of standing postuk. Basal ganglia is also involved in maintaining posture by acting as relay center for extrapyramidal pathways. But its role is not as important. 165. Myelination in peripheral nervous system is done by a) Astrocytes b) Oligodendrocytes c) Ependymal cells d) Schwann cells Correct Answer - D Ans. is d i.e., Schwann cells Myelination in central nervous system → Oligodendrocytes. Myelination in peripheral nervous system → Schwann cell. 166. Sensory perception involves Brodmann's area ? a) 3, 1, 2 b) 4, 6 c) 44, 45 d) 41, 42 Correct Answer - A Ans.A. 3,1,2 Processing of general sensory inputs primarily occurs in primary somatosensory area of parietal lobe. Primary somatosensory area is Brodmann's area 3, 1, 2. 167. Vibrations are felt by ? a) Meissner's corpuscle b) Merkel's disc c) Pacinian corpuscle d) Ruffini's end organ Correct Answer - C Ans. is 'c' i.e., Pacinian corpu