Awesome Semester One MCQs PDF

The Awesome Semester One MCQs **DISCLAIMER: These MCQs are student-made on the topics that are studied in semester one. Intended learning objectives change year to year so they may not all be 100% relevant to what you've learnt. Some of the questions are also quite a bit more difficult than the que...

The Awesome Semester One MCQs **DISCLAIMER: These MCQs are student-made on the topics that are studied in semester one. Intended learning objectives change year to year so they may not all be 100% relevant to what you've learnt. Some of the questions are also quite a bit more difficult than the questions you'll actually get in the exam (especially the first 60 questions), so if you can do them, you're pretty awesome.** 1. Receptors associated with innate immunity recognize microbes by detecting: a. Insulin b. Pathogen associated molecular patterns c. Fc's d. Complement e. None of the above 2. Immunogloblin classes must be distinguished by the type of: f. Light chains they possess. g. Carbohydrate on their light chains. h. Constant regions in their light chains i. Heavy chains they possess j. None of the above 3. The variable regions in the light chains participate in: k. Fc receptor binding l. Epitope binding m. Affinity of the complement receptors n. Interaction of the Fab with cytokines o. None of the above 4. J-chains are associated with: p. IgG q. Polymeric immunoglobulins (more than two Fab's) r. Serum IgA s. IgE t. None of the above. 5. Adoptive-acquired immunity may be the result of: u. Transfer of bone marrow from one individual to another v. Immunization with a vaccine w. Exposure to an individual who has an infectious disease x. A physician administering a gamma globulin shot to someone who has a needle stick (immunoglobulins) y. A and D 6. IgG binding to neutrophil cells is mediated by: z. Fc-dependant cellular homing mechanisms a. Sensitization of Mast cells and basophils b. Fc receptors specific for IgG c. ICAM's d. None of the above 7. IgD participates in antigen recognition by: e. Immature T cells f. NK cells g. Macrophages h. B cells i. None of the above 8. Antibody affinity is not determined by the amino acid sequence in: j. The constant regions of the immunoglobulin molecule k. The variable regions of the immunoglobulin molecule l. The Fc of the immunoglobulin molecule m. The J-chain n. A, c and d. 9. Avidity is important because: o. It amplifies the binding strength of low affinity Fab's p. Fc receptor binding depends on it q. G-protein-mediated signal transduction will not occur without it r. It results in the activation of high affinity antibody producing clones s. None of the above 10. Organized mucosa-associated lymphoid tissue is t. Found in the lymph nodes u. Associated with initial immune response to antigen v. Filled with plasma cells that are producing antibodies w. Composted primary of M-cells and L-cells x. None of the above 11. B cells usually require T cell help to mature plasma cells because: y. T cells present antigen to them z. Most B cells in the circulation need thymic hormones secreted by the antigen presenting cell to mature to plasma cells a. T cells are antigen presenting cells that are critical to immune recognition b. All of the above c. None of the above 12. The antigen presenting cell d. May be a dendritic cell in the skin e. May be a T cell f. Does not produce cytokines which influence the adaptive response g. Matures upon antigenic stimulation and becomes a plasma cell h. All of the above 13. Mucosal immunity provides most of its protection by blocking i. Microbial receptors specific for colonization j. The complement cascade k. Blocking penetration of undigested food products into the mucosal tissues l. A and C m. None of the above 14. Tissue macrophage are mature: n. B cells o. T cells p. NK cells q. Monocytes r. None of the above 15. Hormone-like host peptides used for communications in innate and adaptive immunity are known as: s. PAMPs t. Cell adhesion molecules u. ELISAs v. Cytokines w. None of the above 16. Which of these is not associated with adjuvants?: x. Forms an antigen depot. y. Provides non-specific T cell stimulation z. Activates antigen-presenting cells a. Activates the complement cascade b. None of the above 17. Which is associated with apoptosis c. Regulates cell migration from O-MALT migrate to D-MALT d. Used by T cells to kill target cells e. Mediates necrotic cell death f. A and B g. All of the above are correct responses 18. The lag phase of the secondary response is shorter than the primary response because: h. The assays for detecting a primary response are not as sensitive i. The primary response requires considerable cell proliferation and differentiation to achieve a critical mass of cells to produce immunity j. Of the lack of cytokines produced during the primary response k. A and B l. None of the above 19. The lag phase of the booster response is: m. Very short, due to memory cells n. Very short due to lack of antigen presenting cells o. Very short when dendritic cells are absent p. Very short, due to the presence of accessory cells q. None of the above 20. The location of complement activation is determined by: r. The location of Fc receptors s. The location of dendritic cells t. The location of specific antibody/antigen complexes u. B and C v. None of the above 21. Complement damage is generally limited to the immediate area in which complement is activated because of the: w. Short half-lives of the activated components and their rapid inactivation x. Very low concentrations of the inactivated complement components in serum y. The inability to activate the system in the presence of IgG antibodies z. Once activated, the destructive activities of complement are non-specific a. None of the above 22. During serum sickness, kidney damage occurs as immune complexes form. Why? b. The immune complexes are filtered by the kidneys and damage results from concomitant complement activation and neutrophil activity. c. Antigen presenting cells rapidly bind all of the complexes in their MHC-encoded receptors d. Free antigen activates PAMP receptors in kidneys which rapidly activate adaptive immunity e. The immune complexes bind to Mast cells and are destroyed f. None of the above 23. Contact dermatitis generally occurs against substances that are too small to induce an immune response. How do these substances induce an immune response? g. These substances form deposits and are then slowly released into the blood. h. These low molecular weight substances react with liver enzymes and are difficult to eliminate i. These substances bind to tissues and cells, resulting in a larger total antigenic size which can then stimulate and immune response j. The substances trigger the complement cascade and cause neutrophils to accumulate and to serve as antigen presenting cells k. A and C 24. Your patient tests positive for the tuberculin antigen. You send him for a chest x-ray because: l. The tuberculin test is only presumptive, indication that he has been exposued to tuberculosis antigen m. He may have other lung infections n. You are looking for fluid in his lungs due to inflammation caused by the bacillus o. A and B p. None of the above 25. Which of the following are two hallmarks of the adaptive immune system? q. Immediate and Broad r. Specificity and Memory s. Innate and Short t. Non-specific and Fast u. Immediate and Passive 26. All of the following are true about CD8 T cells **EXCEPT** that they v. Are part of adaptive immunity w. Respond to antigenic peptides presented by MHC class I molecules x. Respond to antigenic peptides presented by MHC class II molecules y. Are major mediators of cytotoxicity against virus-infected host cells z. Can make IFN-gamma 27. All of the following are important functions of Type 1 IFNs **EXCEPT** that they a. Induce resistance to viral infections b. Promote MHC class I expression c. Activate NK cell cytotoxicity d. Are important growth and proliferation factors for B cells e. Are part of the innate defense mechanisms 28. Hematopoetic stem cells are precursor cells for all of the following **EXCEPT** f. Lymphocytes g. Other stem cells h. Erythrocytes i. Vascular smooth muscle cells j. Megakaryocytes 29. IL-12 is important for which of the following k. CD8 expression l. TNF production m. IFN-gamma production n. Eosinophil differentiation o. CD28 expression 30. The thoracic duct p. Facilitates transfer of maternal antibody to the fetus q. Was a major aqueduct in ancient Rome r. Is the lymphocyte port of entry to the blood for the lymphatic system s. Is the Dendritic cell port of entry for travel from the periphery to the lymph node 31. Upon his return from South America, an otherwise Mike a 12 year old boy is found to be infected with helminth parasites. He is doing well because of endogenous Th2 type cytokine response. Which of the following would you expect to see? t. IgA u. CD4 T cell IFN-gamma production v. IL-5 w. IL-12 x. CTL 32. An individual is genetically deficient for the IFN-gamma receptor. Which of the following would you expect to be blocked? y. NK cell development z. Cell surface expression of functional T cell receptor for antigen on mature T cells a. Antimicrobial defense b. IgM antibody responses c. Immunoglobulin gene rearrangement 33. All of the following can be part of the **INNATE** immune responses **EXCEPT** d. Alternate pathway of complement activation e. Natural killer cells f. B cells g. Macrophages 34. The major pathways to Th1 type T cell responses during an infection includes all of the following **EXCEPT** h. CD4 T cells producing IL-5 i. Innate IL-12 j. NK cell IFN-gamma production k. CD4 T cells producing IFN-gamma 35. Which of the following can **NOT** be found in the lymph node? l. Lymphoid follicle m. Red pulp n. B cells o. Cortex p. T cells 36. All of the following are function of IgG **EXCEPT** q. Opsonise bacteria r. Activate complement s. Cross the placenta t. Be secreted into mucus 37. Which of the following require the thymus u. Rearrangement of genes for the T cell antigen receptor and T cell maturation v. Differentiation of granulocytes w. B cell differentiation x. Rearrangement of Germline gene segments to code for variable portions of antibody molecules y. Antigen processing and presentation of material from a peripheral infection 38. Essential steps in cytolytic distruction of target cells by either CTL or NK cells include all of the following **EXCEPT** z. Positive stimulation of cytotoxic cell by target cell a. Delivery of a lethal hit b. Deposition of perforin on the target cell surfaces c. Realse of granzymes from the cytotoxic cells d. Release of IFN-gamma from cytotoxic cells 39. Chemokines are e. Low molecular weight cytokines important in inflammation f. Cytokines important in proliferation g. Activators of complement h. Differentiation of cytokines 40. Which category of hypersensitivity reaction **BEST** describes haemolytic disease of the newborn caused by Rh incompatibility? i. Atopic or anaphylactic j. Cytotoxic k. Immune complex l. Delayed 41. The principal difference between cytotoxic (type II) and immune complex (type III) hypersensitivity is m. The class of (isotype) of antibody n. The site where antigen-antibody complexes are formed o. The participation of complement p. The participation of T cells 42. A child stung by a bee experiences respiratory distress within minutes and lapses into unconsciousness. This reaction is probably mediated by q. IgE antibody r. IgG antibody s. Sensitized T cells t. Complement u. IgM antibody 43. A patient with rheumatic fever develops a sore throat from which beta-hemolytic streptococci are cultured. The patient is started on treatment with penicillin, and the sore throat resolves within several days. However, 7 days after initiation of penicillin therapy the patient develops a fever of 103 degrees F, a generalized rash, and proteinuria. This **MOST** probably resulted from v. Recurrence of the rheumatic fever w. A different infectious disease x. An IgE response to penicillin y. An IgG-IgM response to penicillin z. A delayed hypersensitivity reaction to penicillin 44. A kidney biopsy specimen taken from a patient with acute glomerulonephritis and stained with flourescein-conjucated anti-human IgG antibody would probably show a. No fluorescence b. Uniform fluorescence of the glomerular basement membrane c. Patchy, irregular fluorescence of the glomerular basement membrane d. Fluorescent B cells e. Fluorescent macrophages 45. A patient with severe asthma gets no relief from antihistamines. The symptoms are **MOST** likely to be caused by f. Interleukin-2 g. Slow-reacting substance A (leukotrienes) h. Serotonin i. Bradykinin 46. Hypersensitivity to penicillin and hypersensitivity to poison oak are both j. Mediated by IgE antibody k. Mediated by IgG and IgM antibody l. Initiated by haptens m. Initiated by Th-2 cells 47. Bone marrow transplantation in immunocompromised patients presents which major problem n. Potentially lethal graft-versus-host disease o. High risk of T cell leukemia p. Inability to use a live donor q. Delayed hypersensitivity 48. AIDS is caused by a human retrovirus that kills r. B lymphocytes s. Lymphocyte stem cells t. CD4-positive T lymphocytes u. CD8-positive T lymphocytes 49. Polyomavirus (a DNA virus) causes tumours in "nude mice" (nude mice do not have a thymus, because of a genetic defect) but not in normal mice. The **BEST** interpretation of that is v. Macrophages are required to reject polyomavirus-induced tumours w. Natural killer cells can reject polyomavirus-induced tumours without help from T lymphocytes x. T lymphocytes play an important role in the rejection of polyomavirus-induced tumours y. B lymphocytes play no role in rejection of polyomavirus-induced tumours 50. After binding to its specific antigen, a B lymphocyte may switch its z. Immunoglobulin light-chain isotype a. Immunoglobulin heavy-chain isotype b. Variable region of immunoglobulin heavy chain c. Constant region of the immunoglobulin light chain 51. Diversity is an important feature of the immune system. Which one of the follow statements about it is **INCORRECT** d. Humans can make antibodies without about 108 different VH X VL combinations e. A single cell can synthesize IgM antibody, then switch to IgA antibody f. The haematopoietic stem cell carries the genetic potential to create more than 104 immunoglobulin genes g. A single B lymphocyte can produce antibodies of many different specificities, but a plasma cell is monospecific 52. Neutrophils are attracted to an infected area by h. IgM i. Vascular permeability j. Phagocytosis of IgE coated bacteria k. Aggregation of C4 and C2 53. Complement fixation refers to l. The ingestion of C3b-coated bacteria by macrophages m. The destruction of complement in serum by heating at 56oC for 30 minutes n. The binding of complement components by antigen-antibody complexes o. The interaction of C3b with mast cells 54. Natural killer cells are p. B cells that can kill without complement q. Cytotoxic T cells r. Increased by immunization s. Able to kill virus-infected cells without prior sensitization 55. A positive tuberculin skin test (a delayed hypersensitivity reaction) indicates that t. A humoral immune response has occurred u. A cell-mediated immune response has occurred v. Both the T and B cell systems are functional w. Only the B cell system is functional 56. Reaction to poinsy ivy or poison oak is x. An IgG mediated response y. An IgE mediated response z. A cell-mediated response a. An arthus reaction 57. A delayed hypersensitivity reaction is characterized by b. Oedema without a cellular infiltrate c. An infiltrate composed of neutrophils d. An infiltrate composed of helper T cells and macrophages e. An infiltrate composed of eosinophils 58. The class of immunoglobulin present in highest concentration in the blood of a human newborn is f. IgG g. IgM h. IgA i. IgD j. IgE 59. Cytotoxic T cells induced by infection with virus A will kill target cells k. From the same host infected with any virus l. Infected by virus A and identical at class I MHC loci of the cytotoxic T cells m. Infected by virus A and identical at class II MHC loci of the cytotoxic T cells n. Infected with a different virus and identical at class I MHC loci of the cytotoxic cells o. Infected with a different virus and identical at class II MHC loci of the cytotoxic cells 60. Antigen-presenting cells that activate helper T cells must express which one of the following on their surfaces? p. IgE q. Gamma interferons r. Class I MHC antigens s. Class II MHC antigens 61. Alice your patient became ill 10 days ago with a viral disease. Laboratory examination reveals that the patient's antibodies against this virus have a high ratio of IgM to IgG. What is your conclusion? t. It is unlikely that the patient has encountered this organism previously u. The patient is predisposed to IgE-mediated hypersensitivity reactions v. The information given is irrelevant to previous antigen exposure w. It is likely that the patient has an autoimmune disease 62. Your patient is a child who has no detectable T or B cells. This immunodeficiency is most probably the result of a defect in x. The thymus y. The bursal equivalent z. T cell-B cell interaction a. Stem cells originating in the bone marrow 63. The role of the macrophage during an antibody response is to b. Make antibody c. Lyse virus-infected target cells d. Activate cytotoxic T cells e. Process antigen and present it 64. Each of the following statements concerning class I MHC proteins is correct **EXCEPT** f. They are cell surface proteins on virtually all cells g. They are recognition elements for cytotoxic T cells h. They are codominantly expressed i. They are important in the skin test response to Mycobacterium tuberculosis 65. Each of the following statements concerning class II MHC proteins is correct **EXCEPT** j. They are found on the surface of both B and T cells k. They have a high degree of polymorphism l. They are involved in the presentation of antigen by macrophages m. They have a binding site for CD4 proteins 66. Cancer is often the result of activation of \_\_\_\_\_ to \_\_\_\_\_ and the inactivation of \_\_\_\_ genes n. Oncogenes, tumour-suppressor genes, proto-oncogenes o. Proto-oncogenes, oncogenes, tumour-suppressor genes p. Oncogenes, proto-oncogenes, tumour suppressor genes q. Proto-suppressor genes, suppressors, oncogenes 67. About 50% of all human cancers may involve an abnormal or missing r. Oncogene s. Proto-oncogene t. P53 gene u. BRCA-1 gene 68. Inherited retinoblastoma requires \_\_\_\_ mutation(s) or deletion(s) v. One w. Two x. Three y. Four 69. In which of the human cells listed below is telomerase active? z. Blood a. Bone b. Muscle c. Sperm 70. Which of the following is not a characteristic of cancer cells? d. Loss of cell cycle control e. Transplantability f. Loss of contact inhibition g. All are characteristic 71. The Philadelphia chromosome is associated with which type of cancer? h. Breast i. Thyroid j. Nerve k. Leukemia 72. BRCA-1 is associated with which cancer? l. Breast m. Thyroid n. Nerve o. Leukemia 73. If 85% of lung cancer cases occur in heavy smokers, can lung cancer still have a genetic origin? p. Yes q. No 74. Which of the following statements about telomerase is incorrect? r. It is an enzyme that adds DNA to telomeres s. It serves as the template for telomere lengthening t. It is not activated in cancer cells u. Its activity continually resets the cellular clock 75. Familial cancer is caused by v. A mutation in somatic cells only w. A mutation in germline cells only x. A germline mutation plus a somatic mutation in affected tissue y. Two germline mutations 76. The p53 protein normally promotes z. DNA repair a. Tumour formation b. Cell division c. Apoptoisis 77. The p53 gene is especially prone to d. Point mutation e. Chromosomal rearrangements f. Loss g. None of the above 78. Which type of study compares the incidence of a type of cancer among very different groups of people? h. Population i. Case-control j. Prospective k. Empiric 79. Why is genetic counselling for familial breast cancer difficult? l. BRCA1 and BRCA2 are incompletely penetrant m. Breast cancer can occur in other ways n. Not all mutations are associated with the disease o. All of the above 80. Which of the following is not a traditional cancer treatment p. Blocking telomerase q. Inhibition angiogenesis r. Stimulating specialization s. None of the above 81. Which of the following may contribute to causing cancer? t. A mutation in a gene that slows the cell cycle u. Faulty DNA repair v. Loss of control over telomere length w. All of the above 82. TNM stands for x. Temperature, Metabolism, Nutrition y. Tumour, Nodule, Metastasis z. Tumour, Nerve, Metastasis a. Tumour, Node, Metastasis 83. A patient is suspicious of having breast cancer. What type of test will a physician conduct to diagnose the cancer b. Blood test c. Pap test d. CT scan e. Mammography 84. What is cancer of the bone marrow stem cells that produce white blood cells called? f. Leukaemia g. Sarcoma h. Carcinoma i. Lymphoma 85. Which cells normally kill defective or mutant cells? j. No normal cells can kill a mutant k. Chemokiller cells l. Antibody-producing cells m. Cytotoxic T and natural killer cells 86. A benign epithelial cell neoplasm derived from non-glandular surfaces is referred to as n. Papilloma o. Sarcoma p. Adenoma q. Hamartoma r. Squamous cell carcinoma 87. Which one of the following is not considered to be a distinctive pattern of non-neoplastic growth? s. Regeneration t. Hypertrophy u. Hyperplasia v. Anaplasia w. Metaplasia 88. Which of the following is least likely to be used as a means of distinguishing a benign from a malignant neoplasm? x. Degree of cellular differentiation y. Rate of growth z. Type and amount of necrosis a. Evidence of metastasis b. Mode of spread 89. Which of the following are the most important and clinically useful risk factors for breast cancer? c. Fibrocystic disease, age, and gender d. Cysts, family history in immediate relatives, and gender e. Age, gender, and family history in immediate relatives f. Obesity, nulliparity, and alcohol use 90. Which of the following are true of breast cancer? g. The life time risk of a woman developing breast cancer is 1/9 h. For most women a specific cause of their breast cancer is known i. Prognosis is worse for affluent women j. Incidence of breast cancer is decreasing 91. Risk factor breast cancer include k. Young age l. Young age at menopause m. Young age at first birth n. Young age at first menarche 92. Which of the following statements regarding screening for breast cancer are correct? o. Mammography is offered to all women between the ages of 50 and 75 years in the UK p. Studies have shown an approximate 30% reduction in mortality with screening using mammography q. Most radiographically suspicious lesions are subsequently confirmed as malignant r. Mammography is less sensitive in postmenopausal women 93. Which of the following is not necessary when a patient first presents with a breast lump? s. Fine needle aspiration (FNA) t. Chest x-ray u. Examination of axillary lymph nodes v. Examination of breasts with patient supine 94. Which of the following statements is true regarding adjuvant treatment for early breast cancer? w. Radiotherapy is indicated after breast cancer conserving surgery only if \>4 nodes positive or tumour close to the resection margin x. Aromatase inhibitors are replacing tamoxifen in premenopausal women due to better outcomes and greater tolerability y. Combination chemotherapy reduces recurrence and improves survival in selected patient groups z. No survival benefit has been demonstrated with use of trastuzumab (herceptin) in the adjuvant setting 95. In treatment of metastatic breast cancer a. Chemotherapy is superior to endocrine therapy b. Biphosphonates are used to control hypocalcaemia c. Responses to endocrine therapy tend to occur within 2 months of starting treatment d. Trastuzumab (herceptin) in combination with chemotherapy improves survival in patients who have tumours that overexpress HER-2 96. Which of the following are good prognostic factors in breast cancer? e. Oestrogen receptor positivity f. Grade III tumour g. HER-2 receptor overexpression h. Lymph node involvement 97. Regarding pronator teres which of the following statements is correct? i. It forms the lateral border of the cubital fossa j. It arises from the coronoid process of the lateral epicondyle k. The median nerve passes deep to both heads l. It's medial border forms the medical boundary of the cubital fossa m. It is the most lateral of the superficial of the flexors of the forearm 98. Group three of these forearm flexure muscles into the correct group. Which is the odd one out? n. Flexor pollicis longus o. Pronatos quadrates p. Flexor digitorum profundus q. Flexor digitorum superficialis 99. The radius bone is lateral to the ulna in the anatomical positions r. True s. False 100. The radial styloid process articulates with which of the carpal bones? t. Pisiform u. Lunate v. Trapezoid w. Scaphoid 101. What is the medial boundary of the cubital fossa? x. Pronator teres y. Brachialis z. Brachioradialis a. Supinator 102. The \_\_\_\_\_ muscle is not found in 15% of individuals b. Flexor carpi radialis c. Palmaris retinaculum d. Flexor carpi ulnaris e. Palmaris longus 103. Which of the following muscles of the posterior compartment are innervated directly by the radial nerve? f. Brachioradialis g. Anconeus h. Extensor carpi radialis longus i. Triceps 104. Biceps brachii are well known for being the main flexors of the forearm. However, they are also powerful (1) of the (2) j. 1\. Flexors 2. Humerus k. 1\. Pronators 2. Forearm l. 1\. Extensors 2. Humerus m. 1\. Supinators 2. Forearm 105. Approximately \_\_\_\_ percentage of spontaneous abortions result from extra or missing chromosomes n. 10 o. 25 p. 50 q. 75 106. The most common autosomal aneuploidy is r. Trisomy 13 s. Trisomy 15 t. Trisomy 18 u. Trisomy 21 107. A (an) \_\_\_\_ chromosome has its centromere near a tip so that it has one long arm and one very short arm v. Metacentric w. Submetacentric x. Acrocentric y. None of the above 108. In a (an) \_\_\_\_\_\_, the short arm of two acrocentric chromosomes break, and the long arms join, forming an unusual, long chromosome. z. Robertsonian translocation a. Reciprocal translocation b. Inversion c. Duplication 109. An individual with two normal sets of autosomes and a single X chromosome has d. Down syndrome e. Patau syndrome (don't google image search this) f. Turner syndrome g. Klinefelter Syndrome 110. This structure emanates from the centromere and contacts the spindle fibers during mitosis: h. Alpha satellite i. Subtelomere j. Euchromatin k. Kinetochore 111. Prenatal diagnostic techniques that obtain foetal chromosomes include all but l. Amniocentesis m. Foetal cell sorting n. Chorionic villus sampling o. Flouresence in situ hybridization 112. When chromatids divide along the wrong place, structures with identical arms called \_\_\_\_\_ are formed p. Ring chromosomes q. Translocations r. Isochromosomes s. Satellites 113. In nondisjunction, which parent leads to the aneuploidy XYY t. Mother u. Father v. Either parent w. Both parents 114. An individual with the chromosomal description 45, X would be a x. Normal female y. Female with Turner syndrome z. Male with Klinefelter syndrome a. Cannot be determined 115. Heterochromatic regions at the ends of chromosomes are called b. Centromeres c. Euchromatin d. Telomeres e. Satellites 116. The photographic arrangement of chromosomes is called a (an) f. Karyotype g. Ideogram h. Anagram i. Chromogram 117. A triploid karyotype has how many chromosomes j. 23 k. 46 l. 69 m. 92 118. Nondisjunction of chromosome 21 during meiosis II in human females can result in all of the following chromosome complements in a zygote except (assume the oocyte is fertilized by a sperm with a normal chromosome set) n. No chromosome 21 o. Euploid for chromosome 21 p. Monosomic for chromosome 21 q. Trisomic for chromosome 21 119. About 90% of trisomy 21 Down conceptions are due to nondisjunction during r. Meiosis I in the female s. Meiosis II in the female t. Meiosis I in the male u. Meiosis II in the male 120. Consider the following normal sequence of genes: a b c d e f g h. The sequence of a b f e d c g h represents a (an) v. Deletion w. Duplication x. Inversion y. Translocation 121. Which of the following karyotypes is not possible in the offspring of a translocation carrier (involving chromosomes 14 and 21) and a normal individual z. Deficient 14 or deficient 21 a. Normal b. Translocation Down syndrome c. All are possible outcomes 122. A couple seeks testing and counselling after they have a child with cystic fibrosis. Testing reveals the mother is a carrier but the father is not. How can these results be explained? d. The man tested is not the biological father e. A mutation altered the child's normal allele f. Uniparental disomy (from the mother) g. All are possible explanations, additional testing is needed 123. Which of the following cell types is not used to examine chromosomes? h. White blood cells i. Bone marrow cells j. Red blood cells k. All of the above can be used 124. How many chromosomes does a person with Edward syndrome have? l. 45 m. 46 n. 47 o. 48 125. All the following aneuploids result from female nondisjunction except p. Klinefelter syndrome q. Triplo-X r. Turner syndrome s. Jacobs syndrome 126. Which of the following human genetic disorders is **NOT** caused by nondisjunctions? t. Down syndrome u. Turner Syndrome v. Klinefelter syndrome w. Fragile X syndrome x. Poly X 127. Which of the statements is **NOT** true about X-linked characteristics? y. More males than females are affected z. If a female has the characteristic, all her sons will show it a. Females can be carriers of the gene without showing b. The characteristic often skips a generation, from a woman's father to her son c. Males can have two copies of alleles for the trait, but females can have only one 128. Chorionic villus sampling uses what tissue to analyze the foetal cells and provide a karyotype? d. Foetal blood tissue e. Cells floating in the amniotic fluid f. A small biopsy from the embryo itself but it readily heals g. Membrane tissues from the embryo side of the placenta h. Membrane tissues from the mother's side of the placenta 129. Generally, it is not possible to determine whether nondisjunction failed to occur in oogenesis or spermatogenesis. However, it is possible to assert that \_\_\_\_\_\_\_ resulted in nondisjunction in \_\_\_\_\_\_\_. i. XXY; oogenesis j. XYY; spermatogenesis k. XXX; oogenesis l. XXY; spermatogenesis m. XO; oogenesis 130. Which genetic trait is **NOT** associated with the chromosome involved in Down syndrome? n. Increased incidence of leukaemia o. Cataracts p. Mental retardations q. Alzheimer disease r. Cystic fibrosis 131. Which one of these is caused by repeats of base triplets rather than a whole chromosome? s. Down syndrome t. Edward syndrome u. Klinefelter syndrome v. Fragile-X syndrome w. Turner syndrome 132. Foetal growth\... x. Accelerates in the third trimester y. Is independent of maternal nutrition z. Is independent of maternal size a. Is most rapid in early gestation b. Requires placental amino acid transport to be constant 133. The pancreas\... c. Has acini formed from 5-8 pyramidal-shaped cells d. Has large numbers of myoepithelial cells e. Has a minor exocrine and a major endocrine part f. Secretes an acidic enzyme-rich fluid g. Secretes enzymes via the process of endocytosis 134. In the penis\... h. Each crus of the penis is attached to the ilial ramus i. Nitric oxide causes muscle contraction j. Parasympathetic function is important for erection k. The corpus cavernosum is pierced by the urethra l. The penile portion of the urethra is lined by squamous epithelium 135. Atopic asthma\... m. Initiates IgE antibody synthesis n. Is an example of a type II hypersensitivity response o. Is an example of a type III hypersensitivity response p. Is associated with high levels of IgM q. Is associated with mast cell degranulation in the lung 136. Memory B cells\... r. Are found primarily in the red pulp of the spleen s. Generally produce IgM t. Have short life spans u. Recirculate in the blood between spleen and lymph nodes v. Reside permanently in germinal centres 137. MHC class II molecules\... w. Are absent from the thymus x. Are constitutively expressed only on specialised antigen presenting cells y. Are expressed on all cells except those of the nervous system z. Are formed by an alpha chain and beta-2 microglobulin a. Bind endogenous peptides 138. Cells that enter the lymph nodes by migrating across high endothelial venules include b. CD4+ T cells c. Neutrophils d. Plasma cells e. Platelets f. Red blood cells 139. Farah, daughter of an obligate carrier of an X-linked recessive condition, is pregnant. Assuming that Farah's father and the unborn child's father are unaffected the chance that Mary's child will have the X-linked recessive condition is g. 1 in 16 h. 1 in 8 i. 1 in 4 j. 1 in 2 k. None 140. A 5 year-old boy has a severe sore throat, high fever and cervical lymphadenopathy. It is suspected that the causative agent is Streptococcus pyogenes. Prior to initiation of antibiotic therapy, the child is gen asprin to reduce fever. The mechanism of fever reduction by asprin is l. Increasing the hypothalamic set-point temperature m. Inhibition of prostaglandin synthesis n. Shivering o. Shunting of blood from the surface of skin p. Stimulation of cyclo-oxygenase 141. This image is a section from the skin. The region indicated by X is the q. Dermis r. Epidermis s. Epidermal ridge t. Grainy layer u. Junction between the dermis and epidermis 142. The form of RNA that brings amino acids to the protein synthesis machinery is called v. mRNA w. miRNA x. rRNA y. siRNA z. tRNA 143. Nonsense mutations a. Cause a frameshift b. Alter an amino acid coded for by a particular codon c. Cause premature termination of the protein chain d. Cause promoters to become inactive e. Result in more severe phenotype than missense mutations 144. In relation to growth during puberty\... f. Both boys and girls have their growth spurts at the same time g. Boys finish growth before girls h. Bows grow more than girls i. Girls grow faster than boys j. Girls have their growth spurt at menarche 145. Surgical removal of the seminal vesicles would k. Cause sterility because sperm production would cease l. Cause sterility because sperm would remain in the male reproductive tract m. Have minimal effect on semen volume n. Result in increased likelihood of pregnancy with the withdrawal method of birth control o. Result in semen lacking energy-providing nutrients for sperm 146. Embryonic ectoderm gives rise to p. Cartilage q. Dermis r. Gut epithelium s. Neural crest cells t. Vascular endothelium 147. "Non-directive" genetic counselling involves providing advice to people affected by a genetic disorder, principally so that they can\... u. Assess the pros and cons of the different options v. Reach a decision in their own time w. Reach and independent decision x. Reach a reasoned outcome y. Reach the most acceptable decision 148. An adolescent experiences a delay in developing secondary sexual characteristics. His testosterone levels are tested and found to be normal. A possible cause for his problem may be\... z. Decreased levels of a cell membrane testosterone receptor a. Decreased levels of a serum testosterone binding protein b. Decreased levels of intracellular testosterone binding protein c. Inability to produce second messenger signal molecules after the binding of testosterone to its cell membrane receptor d. Loss of function of a tyrosine kinase 149. The T cell receptor on CD4+ T cells e. Changes class upon T cell activation f. Is secreted to recognise antigen in association with MHC g. Recognises antigenic peptide in association with class I MHC h. Recognises antigenic peptide in association with class II MHC i. Recognises parts of DNA 150. Antibody class is determined by the j. Antigen binding site k. Constant heavy chain region l. Hypervariable region m. J chains n. Light chains 151. Loss of heterozygosity can be described as o. An inherited chromosomal abnormality p. Deletion of a whole chromosome q. Losing one allele r. Meiotic recombination s. Switching to a haploid state 152. Cells are most susceptible to radiation damage when in the t. G0 phase of the cell cycle u. G1 phase of the cell cycle v. G2 phase of the cell cycle w. M phase of the cell cycle x. S phase of the cell cycle 153. The matrix of bone is primarily composed of y. Calcium phosphate and hydroxapatite z. Collagen fibres and calcium phosphate a. Osteocytes, collagen and calcium ions b. Type I collage and calcium carbonate c. Type II collagen and calcium salts 154. In a normal distribution, the percentage of values that lie between plus one and minus one standard deviation of the mean is approximately d. 2.5% e. 5% f. 34% g. 68% h. 95% A 5 year old girl developed prominent nipples about a year ago and now has noticeable breast development. Her height is 115cm (91^st^ percentile) and mid-parental height is 163cm (50^th^ centile). 155. Breast development results directly from increased secretion of: i. Oestrogen j. FSH k. LH l. Progesterone m. Prolactin 156. As an adult, she is most likely to be n. Average height o. Overweight p. Short q. Tall r. Underweight  This is a transverse section through the hand that really loves coming up in exams 157. The distal carpal bone A is the s. Capitates t. Hamate u. Lunate v. Scaphoid w. Trapezoid 158. In the anatomical position, B represents the x. Dorsal surface of the hand y. Lateral surface of the hand z. Medial surface of the hand a. Palmar surface of the hand b. Ventral surface of the hand 159. A month-old baby would rather look at a face than a neutral stimulus, this is an example of c. Genetic predisposition d. Inborn preference e. Inherent f. Learned response g. Maturation h. Nature versus nuture i. Reflex 160. Some changes in ability are due to increasing age alone, this is an example of j. Genetic predisposition k. Inborn preference l. Inherent m. Learned response n. Maturation o. Nature versus nuture p. Reflex 161. A man with familial hypercholesterolaemia is very likely to develop heart disease, this is an example of q. Genetic predisposition r. Inborn preference s. Inherent t. Learned response u. Maturation v. Nature versus nuture w. Reflex 162. The peritoneum reflected from the side of the uterus to the lateral walls of the pelvis is the x. Broad ligament y. Perimetrium z. Rectouterine pouch a. Round ligament b. Uterosacral ligament 163. What prevents the body of the uterus from moving ateriorly and inferiorly c. Broad ligament d. Perimetrium e. Rectounterine pouch f. Round ligament g. Uterosacral ligament 164. A man carries a mutation in one copy of a gene coding for a membrane protein essential for normal lung function. His wife has two copies of this gene. What is the probability that their unborn son will suffer from lung disease if the mutation is autosomal dominant h. 0 i. 0.25 j. 0.5 k. 0.75 l. 1 165. Same scenario as **164** but the mutation is autosomal recessive m. 0 n. 0.25 o. 0.5 p. 0.75 q. 1 166. Same scenario as **164** but the mutation is Y-linked r. 0 s. 0.25 t. 0.5 u. 0.75 v. 1 167. Each of the following statements regarding the genetics of cystic fibrosis (CF) is correct **EXCEPT**: w. The CF gene codes for a protein called cystic fibrosis transmembrane regulator (CFTR) x. CFTR is largely expressed in epithelial cells of the airways, the pancreas, the biliary system, the genitourinary system, and the sweat glands y. Although there are a few hundred mutations that exist for CF, the most prevelant among northern Europeans is W1282X z. Severity of lung disease and liver disease cannot be predicted by genotype 168. Which of the following exocrine glandular ducts are **NOT** obstructed in cystic fibrosis a. Pancreas b. Lungs c. Sweat glands d. Glands of the uterine cervix 169. Which of the following is **NOT** a pulmonary complication of CF? e. Massive hemoptysis and pneumothorax f. Atelectasis and acute respiratory failure g. Allergic bronchopulmonary aspergillosis and hypertrophic pulmonary osteoarthorapathy h. Lymphangiomyomatosis and chylothorax 170. Each of the following statements regarding pregnancy in women with CF is correct **EXCEPT** i. Impairment of pulmonary function is the major predictor of both maternal and foetal outcome j. CF patients have an increased risk for premature delivery k. The maternal and foetal outcome is good for most cystic fibrosis patients l. The pregnancy need not be a planned one 171. CF affects which body system? m. Circulatory system n. Respiratory system o. Digestive system p. Nervous system q. *b* and *c* 172. Which symptom in an infant or young child might indicate CF? r. Abnormal stools that may be pale, foul or float s. Frequent wheezing or pneumonia t. Salty-tasting skin u. Chronic cough v. All of the above 173. What happens to the mucus glands in a child with CF? w. Too little mucus is produced x. The mucus produced is too thing y. The mucus produced it too thick z. The mucus accumulates in the body a. *c* and *d* 174. How is the digestive system affected by excess mucus in CF? b. The mucus can cause stomach ulcers c. The mucus can damage the bile ducts in the liver d. The mucus can clog the ducts in the pancreas e. The mucus can damage the rectum f. *b* and *c* 175. How is CF diagnosed? g. Sweat test h. Blood test i. Lung volume test j. Urine test k. *a* and *b* 176. Currently no effective treatment is available to correct the cause of CF. Doctors can, however, slow the progression of the disease. Which of these types of medication can do this? l. Bronchodilators m. Antibiotics n. Decongestants o. Mucolytics p. All of the above 177. Modeling is enhanced when the person being modelled is q. A low-status person r. Attractive s. Speaking a foreign language t. A social isolate u. A child 178. People's expectations that they are capable of performing a behaviour that will produce desired outcomes in any particular situation is called v. Outcome expectancy w. Self-efficacy x. Distortion of consequences y. The self-system 179. Which technique is **LEAST** likely to increase a person's self-efficacy? z. Verbal persuasion a. Increased emotional arousal b. Vicarious experiences c. Performance accomplishments 180. Which of these is **MOST** likely to increase self-efficacy d. Verbal persuasion e. Increased emotional arousal f. Decreased emotional arousal g. Performance accomplishments 181. Wallston (1978) has described three dimensions of (multi-dimensional) health locus of control. These are: h. Internal, external, and powerful others i. External, powerful others, and self-efficacy j. Powerful others, internal, and self-efficacy k. Internal, self-efficacy, and external 182. The behaviour of people around us creates a perceived: l. Attitude m. Social normal n. Value o. Intention 183. Attitudes consist of three related parts. What are they? p. Influence, emotion, and perception q. Thought, emotion, and behaviour r. Emotion, behaviour, and influence s. Thought, influence, and emotion 184. Connor says "I use condoms more regularly than most of my friends, so my risk of contracting a STD is low". This is an example of: t. Social normal u. Self-efficacy v. Unrealistic optimism w. External health locus of control 185. "Exercise will make me fitter" is an example of: x. A goal y. Unrealistic optimism z. An outcome expectancy a. Self-regulation 186. Which of the following is **NOT** a component of the health belief model? b. Perceived barriers c. Perceived susceptibility d. Perceived behaviour control e. Perceived severity 187. Which of the following is **NOT** a criticism of the health belief model? f. It overlooks the role of disease severity g. It assumes human beings are rational h. It underestimates the role of social influence i. It overestimates the role of threat 188. According to the health belief model, women who perform regular breast self-examinations (BSE): j. Believe that the benefits of BSE outweigh the barriers to them k. Believe that they are susceptible to breast cancer l. Believe that developing breast cancer would have serious effects m. All of the above 189. The \_\_\_\_\_ report was the first British publication to identify poverty as a cause of ill health n. Brown o. Black p. Red q. White 190. The provision of healthcare differences according to where you live is known as the r. County lottery s. Area lottery t. Postcode lottery u. Health authority lottery 191. What are the five consistent themes of 'illness representations' as identified by Leventhal? v. Identity, consequences, cause, timeline and curability/controllability w. Identity, coping, cause, timeline, and curability/controllability x. Identity, consequences, cause, coping, and curability/controllability y. Identity, consequences, coping, timeline, and curability/controllability 192. Which of the following is an example of a cognitive schema? z. Sorting by colour a. Grasping a rattle b. Looking at an object c. Sucking a pacifier 193. According to Piaget, the incorporation of new information into existing schemas is called: d. Operational thought e. Equilibration f. Accommodation g. Assimilation 194. Tim likes to explore his parent's house through touch. One day he touches the oven and burns his hand. Tim learns that although some objects are safe to touch, ovens are not. According to Piaget, this is an example of: h. Assimilation i. Accommodation j. Negative reinforcement k. Positive reinforcement 195. How many stages of cognitive development did Piaget identify? l. Three m. Four n. Five o. Six 196. When Mat was 5 months old, he looked at a toy train, but when his view of the train was blocked, he did not search for it. Now that he is 9 months old, he does search for it, reflecting his development of: p. Object permanence q. Self-differentiation r. Assimilation s. Schemata 197. Evie understands that her father can also be a son and a brother, all at the same time. This suggests that Evie is in the: t. Sensorimotor stage u. Preoperational stage v. Concrete operational stage w. Formal operational stage 198. In Piagetian terms, the cognitive ability to solve problems that develop in adolescence is called: x. Trial-and-error reasoning y. Hypothetical-deductive reasoning z. Concrete thinking a. Transitivity 199. Chieun, a preschooler, insists on dressing herself each morning for school, even though she generally selects mismatching outfits, misses buttons, and wears her shoes on the wrong feet. When her mother tries to dress Chieun or fix her outfit, Chieun brushes her mother off and insists on doing it herself. What stage of psychosocial behaviour best describes Chieun's behaviour? b. Trust vs. Mistrust c. Autonomy vs. Shame and Doubt d. Initiative vs. Guilt e. Industry vs. Inferiority 200. The central theme of Erikson's theory of psychosocial stages was the development of f. Personality g. Psychosocial conflict h. Social status i. Ego identity 201. At each stage of Erikson's theory of psychosocial development, people experience a (an) \_\_\_\_\_\_\_\_ that serves as a turning point. j. Epiphany k. Conflict l. Paradigm shift m. Turmoil 202. The stage that occurs between birth and one year of age is concerned with n. Trust vs. Mistrust o. Autonomy vs. Shame and Doubt p. Initiative vs. Guilt q. Identity vs. Role confusion 203. Erikson believed that people move through a series of \_\_\_\_ psychosocial stages throughout the lifespan. r. Four s. Eight t. Ten u. Twelve 204. The crisis that arises in young adulthood is concerned with v. Trust vs. Mistrust w. Industry vs. Inferiority x. Integrity vs. Despair y. Intimacy vs. Isolation 205. Eight year old Raj has a difficult time making friends at school. He has trouble completing his schoolwork accurately and on time, and as a result, receives little positive feedback from his teacher and parents. According to Erikson's theory, failure at this stage of development results in \_\_\_\_\_\_\_\_? z. Feelings of inferiority a. A sense of guilt b. A poor sense of self c. Mistrust 206. The central conflict in the eight stage of Erikson's theory focuses on Integrity vs. Despair and involves reflecting back on your life. Those who are unsuccessful at resolving this conflict will look back with regret, anger, and bitterness. Those who are successful will feel a sense of satisfaction with the life they have lived. According to Erikson, those who are successful in this stage emerge with \_\_\_\_\_\_\_\_\_. d. Hope e. Fidelity f. Purpose g. Wisdom 207. Which is the dominant cell type in the paracortex of lymph nodes? h. Adipocyte i. Mast cell j. T-lymphocyte k. M-cell 208. What tissue type is pictured here to the right? l. Simple columnar epithelium m. White adipose tissue n. Keratinized stratified squamous epithelium o. Unicellular exocrine gland (goblet cell) 209. Which cell type releases histamine? p. Mast cell q. Fibrocyte r. Mesenchymalcell s. Reticular cell  210. What tissue type is pictured here to the right? t. Stratified sqaumous epithelium u. Simple columnar epithelium v. Stratified cuboidal epithelium w. Simple squamous epithelium 211. What tissue type is pictured here to the right? x. Loose irregular connective tissue y. White adipose tissue z. Dense irregular connective tissue a. Mesenchymal connective tissue 212. Sperm pass through all the following structures **EXCEPT** the \_\_\_\_\_\_\_ b. Ductus deferens c. Ejaculatory duct d. Urinary bladder e. Urethra 213. Following delivery, which pair of hormones is most closely associated with lactation? f. Prolactin and oxytocin g. Oestrogen and prolactin h. Progesterone and prolactin i. Oestrogen and progesterone 214. Immature egg cells are called \_\_\_\_\_\_\_ j. Graafian cells k. Follicles l. Fimbriae m. Oocytes 215. Sperm are produced in the \_\_\_\_\_\_\_\_ n. Prostate gland o. Vas deferens p. Seminiferous tubules q. Epididymis 216. Which hormone, produced by the early embryo that makes the corpus luteum persist in the ovary, is tested for in a pregnancy test? r. Testosterone s. Oxytocin t. Lutenizing hormone (LH) u. Human chorionic gonadotropin (HCG) 217. Which pituitary hormone stimulates ovulation and can be used to predict the time of ovulation? v. Progesterone w. Lutenizing hormone (LH) x. Follicle-stimulating hormone (FSH) y. HCG 218. The receptor for steroid hormones lies z. In the cytoplasm a. Within the plasma membrane b. Within the nuclear envelope c. In the blood plasma 219. Second messengers are activated in response to d. Steroid hormones e. Thyroxine f. Peptide hormones g. All of these 220. Which of the following hormones is not released by the anterior pituitary? h. Melanocyte-stimulating hormone i. Gonadotrophin-releasing hormone j. Thyroid-stimulating hormone k. Growth hormone 221. \_\_\_\_\_\_ hormone stimulates the adrenal cortex to produce several of its hormones l. Follicle-stimulating m. Luteinizing n. Adrenocorticotropic o. Growth 222. Parathyroid hormone acts to ensure that p. Calcium levels in the blood never drop too low q. Sodium levels in urine are constant r. Potassium levels in the blood don't escalate s. The concentration of water in the blood is sufficient 223. The adrenal cortex release \_\_\_\_\_\_\_, which stimulates Na+ reabsorption by the kidneys t. Epinephrine u. Aldosterone v. Glucose w. Cortisol 224. Individuals with type I diabetes x. Lack beta cells in the iselets of Langerhans y. Produce enough insulin but lack functional receptors on their cells z. Can control their diabetes with diet and exercise a. All of the above 225. Which of the following hormones is **NOT** important in calcium homeostasis? b. Calcitonin c. Parathyroid hormone d. 1,25-dihydrocyholecalciferol e. Glucagon 226. Which of the following statements regarding calcium homeostasis is **NOT** true? f. Extracellular calcium concentration is monitored by the parathyroid g. Inhibition of osteoclast activity helps restore high extracellular calcium concentration to normal levels h. Calcitonin and parathyroid hormone have opposing effects on extracellular calcium concentration i. 1,25-dihydrocycholecalciferol and parathyroid hormone have opposing effects on extracellular calcium concentration **ANSWERS:** **1** b --------- --- **2** d **3** b **4** b **5** a **6** c **7** d **8** e **9** a **10** b **11** e **12** a **13** d **14** d **15** d **16** d **17** b **18** b **19** a **20** c **21** a **22** a **23** c **24** a **25** b **26** c **27** d **28** d **29** c **30** c **31** c **32** c **33** c **34** a **35** b **36** d **37** a **38** e **39** a **40** d **41** b **42** a **43** d **44** c **45** b **46** c **47** a **48** c **49** c **50** b **51** d **52** c **53** c **54** d **55** b **56** c **57** c **58** A **59** b **60** D **61** A **62** D **63** d **64** d **65** a **66** b **67** c **68** b **69** d **70** d **71** d **72** a **73** a **74** c **75** c **76** d **77** a **78** a **79** d **80** d **81** d **82** b **83** d **84** a **85** d **86** a **87** d **88** c **89** c **90** a **91** d **92** b **93** b **94** c **95** d **96** a **97** e **98** d **99** a **100** d **101** a **102** d **103** a **104** d **105** c **106** d **107** c **108** a **109** c **110** d **111** d **112** c **113** b **114** b **115** c **116** a **117** c **118** a **119** a **120** c **121** d **122** d **123** c **124** c **125** d **126** d **127** e **128** d **129** b **130** e **131** d **132** a **133** a **134** c **135** e **136** d **137** b **138** a **139** c **140** b **141** e **142** e **143** c **144** c **145** e **146** d **147** c **148** c **149** d **150** b **151** c **152** d **153** b **154** c **155** a **156** c **157** b **158** b **159** b **160** e **161** a **162** a **163** e **164** c **165** a **166** e **167** c **168** c **169** d **170** d **171** e **172** e **173** e **174** e **175** e **176** e **177** b **178** b **179** b **180** d **181** a **182** b **183** b **184** c **185** c **186** c **187** a **188** d **189** c **190** c **191** a **192** a **193** d **194** b **195** b **196** a **197** c **198** b **199** b **200** d **201** b **202** a **203** b **204** d **205** a **206** d **207** c **208** c **209** a **210** a **211** c **212** c **213** a **214** d **215** c **216** c **217** b **218** a **219** c **220** b **221** c **222** a **223** b **224** a **225** d **226** d