Human Anatomy and Physiology Lab Manual PDF

P age |1 Laboratory Manual Human Anatomy and Physiology Course code: 21BBT302/ 21IMBT302 P age |2  P age |3 INDEX SR.N TITTLE PAGE Marks Sign O....

P age |1 Laboratory Manual Human Anatomy and Physiology Course code: 21BBT302/ 21IMBT302 P age |2  P age |3 INDEX SR.N TITTLE PAGE Marks Sign O. NO. 1. HUMAN SKELETAL SYSTEM 2. CIRCULATORY SYSTEM 3. GASTRO INTESTINAL SYSTEM 4. EXCRETORY SYSTEM 5. RESPIRATORY SYSTEM 6. NERVOUS SYSTEM 7. BLOOD PRESSURE AND PULSE RATE MEASUREMENT 8. ABO BLOOD GROUP TESTING P age |4  P age |5 PRACTICLE NO. 01 HUMAN SKELETAL SYSTEM 1. DIVISION OF HUMAN SKELETAL SYSTEM: The skeletal system includes all the bones, cartilages, and ligaments of the body that support and give shape to the body and body structures. The human skeleton is the internal framework of the human body. It is composed of around 270 bones at birth – this total decreases to around 206 bones by adulthood after some bones get fused together. The bone mass in the skeleton reaches maximum density around age 21.  P age |6 The skeleton is subdivided into two major divisions 1. Axial skeleton 2. Appendicular skeleton 1. AXIAL SKELETON: a.) The axial skeleton forms the vertical, central axis of the body and includes all bones of the head, neck, chest, and back. b.) It serves to protect the brain, spinal cord, heart, and lungs. It also serves as the attachment site for muscles that move the head, neck, and back, and for muscles that act across the shoulder and hip joints to move their corresponding limbs. c.) The axial skeleton of the adult consists of 80 bones, including the skull, the vertebral column, and the thoracic cage. The skull is formed by 22 bones. d.) Also associated with the head are an additional seven bones, including the hyoid bone and the ear ossicles (three small bones found in each middle ear). e.) The vertebral column consists of 24 bones, each called a vertebra, plus the sacrum coccyx. The thoracic cage includes the 12 pairs of ribs, and the sternum, the flattened bone of the anterior chest. 2. APPENDICULAR SKELETON: a.) The appendicular skeleton includes all bones of the upper and lower limbs, plus the bones that attach each limb to the axial skeleton. b.) There are 126 bones in the appendicular skeleton of an adult.  P age |7 2. CLASSIFICATION OF BONES ACCORDING TO THE SHAPE OF THE BONE: The classification of bones according to their shape are: 1. Long Bones 2. Short Bones 3. Flat Bones 4. Irregular Bones 5. Sesamoid Bones Described as: 1. Long bones: a.) A long bone is one that is cylindrical in shape, being longer than it is wide. Keep in mind, however, that the term describes the shape of a bone, not its size. b.) Long bones are found in the arms (humerus, ulna, radius) and legs (femur, tibia, fibula), as well as in the fingers (metacarpals, phalanges) and toes (metatarsals, phalanges). Long bones function as levers; they move when muscles contract. 2. Short Bones: a.) A short bone is one that is cube-like in shape, being approximately equal in length, width, and thickness. b.) The only short bones in the human skeleton are in the carpals of the wrists and the tarsals of the ankles. c.) Short bones provide stability and support as well as some limited motion. 3. Flat bones: a.) The term flat bone is somewhat of a misnomer because, although a flat bone is typically thin, it is also often curved. b.) Flat bones serve as points of attachment for muscles and often protect internal organs. c.) Examples include the cranial (skull) bones, the scapulae (shoulder blades), the sternum (breastbone), and the ribs. 4. Irregular Bones: a.) An irregular bone is one that does not have any easily characterized shape and therefore does not fit any other classification. b.) These bones tend to have more complex shapes, like the vertebrae that support the spinal cord and protect it from compressive forces.  P age |8 c.) Many facial bones, particularly the ones containing sinuses, are classified as irregular bones. d.) Certain irregular bones contain large air spaces lined by epithelium, called Pneumatic bones 5. Sesamoid bone: a.) A sesamoid bone is a small, round bone that, as the name suggests, is shaped like a sesame seed. b.) These bones form in tendons (the sheaths of tissue that connect bones to muscles) where a great deal of pressure is generated in a joint. c.) The sesamoid bones protect tendons by helping them overcome compressive forces. d.) Sesamoid bones vary in number and placement from person to person but are typically found in tendons associated with the feet, hands, and knees.  P age |9 Diagram  P a g e | 10 3. SKULL BONES: The adult human skull is comprised of twenty-two bones which are divided into two parts of differing embryological origin: the neurocranium and the viscerocranium. 1. Neurocranium: The neurocranium forms the cranial cavity that surrounds and protects the brain and brainstem. The neurocranium is formed from the occipital bone, two temporal bones, two parietal bones, the sphenoid, ethmoid and frontal bones; they are all joined together with sutures. 2. Viscerocranium: The viscerocranium bones form the anterior and lower regions of the skull and include the mandible, which attaches through the only truly motile joint found in the skull. The facial skeleton contains the vomer, two nasal conchae, two nasal bones, two maxilla, the mandible, two palatine bones, two zygomatic bones, and two lacrimal bones. Cranial bones: The neurocranium is comprised of eight bones: occipital, two temporal bones, two parietal bones, sphenoid, ethmoid, and the frontal bone. 1. Occipital Bone: a.) The occipital bone forms the base of the skull at the rear of the cranium. It articulates with the first vertebra of the spinal cord and also contains the foramen magnum, the large opening of the skill through which the spinal cord passes as it enters the vertebral column. b.) The occipital bone borders the parietal bones through the heavily serrated lambdoidal suture, and also the temporal bones through occipitomastoid suture. 2. Temporal Bones: The temporal bones are situated at the base and sides of the skull, lateral to the temporal lobes of the brain.  P a g e | 11 The temporal bones consist of four regions the squamous, mastoid, petrous and tympanic regions. The squamous region is the largest and most superior region. Inferior to the squamous is the mastoid region, and fused between the squamous and mastoid regions is the petrous region. Finally, the small and inferior tympanic region lies anteriorly to the mastoid. There are two processes that originate from the temporal bone: 1. The zygomatic process that projects from the lower squamous region and articulates with the zygomatic bone of the cheek. 2. The styloid process projects downwards from the interior of the temporal bone and provides attachment for several muscles associated with the tongue. The temporal bones have four borders: 1. The occipitomastoid suture separates the occipital bone and mastoid portion of temporal bone. 2. The squamosal suture separates the parietal bone and squama portion of temporal bone. 3. The sphenosquamosal suture separates the sphenoid bone and squama portion of temporal bone. 4. The zygomaticotemporal suture separates the zygomatic bone and zygomatic process of temporal bone. 3. Parietal Bones: a.) The two large parietal bones are connected and make up part of the roof and sides of the human skull. b.) The two bones articulate to form the sagittal suture. In the front, the parietal bones form the coronal suture with the frontal bone, and in the rear, the lambdoid suture is formed by the occipital bone. c.) Finally, the squamosal suture separates the parietal and temporal bones. 4. Sphenoid Bone: a.) The sphenoid bone is situated in the middle of the skull towards the front and forms the rear of the orbit. It has been described as resembling a butterfly due to its wing-like processes.  P a g e | 12 b.) The sphenoid bone is divided into several parts: the body of the bone, two greater wings, two lesser wings, and the pterygoid processes. c.) The sphenoid bone is one of the most complex in the body due to its interactions with numerous facial bones, ligaments, and muscles. d.) The body that forms the middle of the sphenoid bone articulates with the ethmoid and occipital bone and forms a key part of the nasal cavity; it also contains the sphenoidal sinuses. e.) The greater wings form the floor of the middle cranial fossa that houses the frontal lobes and pituitary gland, and also the posterior wall of the orbit. f.) The lesser wings project laterally and form the floor of the anterior cranial fossa and the superior orbital fissure through which several key optical nerves pass. 5. Ethmoid Bone: a.) The ethmoid bone is a small bone in the skull that separates the nasal cavity from the brain. b.) It is lightweight due to its spongy, air-filled construction and is located at the roof of the nose and between the two orbits. c.) The ethmoid bone forms the medial wall of the orbit, the roof of the nasal cavity, and due to its central location it articulates with numerous bones of the viscerocranium. d.) Inside the neurocranium it articulates with the frontal and sphenoid bones. 6. Frontal Bone: The frontal bone forms the front of the skull and is divided into three parts: 1. Squamous: This part is large and flat and forms the main region of the forehead. 2. Orbital: This part lies inferiorly and forms the superior border of the orbit. 3. Nasal: this part is smaller and articulates with the nasal bones and maxilla to contribute to the roof of the nose. The frontal bone borders two other neuro-cranial bones i. the parietal bones through the coronal sutures  P a g e | 13 ii. the sphenoid bone through the sphenofrontal suture. It also articulates with the zygomatic and nasal bones and the maxilla. Diagram  P a g e | 14 4. VERTEBRAL COLUMN: The vertebral column is also known as the spinal column or spine. It consists of a sequence of vertebrae, each of which is separated and united by an intervertebral disc. Together, the vertebrae and intervertebral discs form the vertebral column. The total number of vertebrae during early development is 33. As a child grows, several vertebrae in the sacral and coccygeal regions fuse. As a result, the adult vertebral column typically contains 26 vertebrae. These are distributed as follows: 7 cervical vertebrae (cervic- = neck): in the neck region. 12 thoracic vertebrae (thorax = chest): posterior to the thoracic cavity. 5 lumbar vertebrae (lumb- = loin): supporting the lower back. 1 sacrum: consisting of five fused sacral vertebrae. 1 coccyx: usually consisting of four fused coccygeal vertebrae. The cervical, thoracic, and lumbar vertebrae are movable, but the sacrum and coccyx are not. REGIONS OF A TYPICAL VERTEBRAL COLUMN ARE: 1. Cervical Vertebrae: a.) The bodies of the cervical vertebrae (C1–C7) are smaller than all other vertebrae except those that form the coccyx. b.) Their vertebral arches, however, are larger. All cervical vertebrae have three foramina: one vertebral foramen and two transverse foramina. c.) The vertebral foramina of cervical vertebrae are the largest in the spinal column because they house the cervical enlargement of the spinal cord. d.) Each cervical transverse process contains a transverse foramen through which the vertebral artery and its accompanying vein and nerve fibres pass. 2. Thoracic Vertebrae: a.) Thoracic vertebrae (T1–T12) are considerably larger and stronger than  P a g e | 15 cervical vertebrae. b.) In addition, the spinous processes on T1 through T10 are long, laterally flattened, and directed inferiorly. c.) In contrast, the spinous processes on T11 and T12 are shorter, broader, and directed more posteriorly. Compared to cervical vertebrae, thoracic vertebrae also have longer and larger transverse processes. d.) They are easily identified by their costal facets, which are articular surfaces for the ribs. e.) The feature of the thoracic vertebrae that distinguishes them from other vertebrae is that they articulate with the ribs. Except for T11 and T12, the transverse processes of thoracic vertebrae have costal facets that articulate with the tubercles of the ribs. 3. Lumbar Vertebrae: a.) The lumbar vertebrae (L1–L5) are the largest and strongest of the unfused bones in the vertebral column because the amount of body weight supported by the vertebrae increases toward the inferior end of the backbone. b.) Their various projections are short and thick. c.) The superior articular processes are directed medially instead of superiorly, and the inferior articular processes are directed laterally instead of inferiorly. d.) The spinous processes are quadrilateral in shape, are thick and broad, and project nearly straight posteriorly. The spinous processes are well adapted for the attachment of the large back muscles. 4. Sacral and Coccygeal Vertebrae: a.) The sacrum is a triangular bone formed by the union of five sacral vertebrae (S1–S5). The sacral vertebrae begin to fuse in individuals between 16 and 18 years of age, a process usually completed by age 30. b.) Positioned at the posterior portion of the pelvic cavity medial to the two hip bones, the sacrum serves as a strong foundation for the pelvic girdle. c.) The female sacrum is shorter, wider, and more curved between S2 and S3 than the male sacrum. d.) The concave anterior side of the sacrum faces the pelvic cavity. It is smooth and contains four transverse lines (ridges) that mark the joining of the sacral  P a g e | 16 vertebral bodies. e.) At the ends of these lines are four pairs of anterior sacral foramina. The lateral portion of the superior surface of the sacrum contains a smooth surface called the sacral ale which is formed by the fused transverse processes of the first sacral vertebra (S1). f.) The coccyx, like the sacrum, is triangular in shape. It is formed by the fusion of usually four coccygeal vertebrae. g.) The coccygeal vertebrae fuse somewhat later than the sacral vertebrae, between the ages of 20 and 30. h.) The dorsal surface of the body of the coccyx contains two long coccygeal cornua that are connected by ligaments to the sacral cornua. i.) The coccygeal cornua are the pedicles and superior articular processes of the first coccygeal vertebra. They are on the lateral surfaces of the coccyx, formed by a series of transverse processes; the first pair are the largest. The coccyx articulates superiorly with the apex of the sacrum. j.) In females, the coccyx points inferiorly to allow the passage of a baby during birth; in males, it points anteriorly. INTERVERTEBRAL DISCS: a.) Intervertebral discs are found between the bodies of adjacent vertebrae from the second cervical vertebra to the sacrum and account for about 25% of the height of the vertebral column. b.) Each disc has an outer fibrous ring consisting of fibrocartilage called the annulus fibrosus and an inner soft, pulpy, highly elastic substance called the nucleus pulposus. c.) The superior and inferior surfaces of the disc consist of a thin plate of hyaline cartilage. d.) The discs form strong joints, permit various movements of the vertebral column, and absorb vertical shock. e.) Under compression, they flatten and broaden. NORMAL CURVES OF HUMAN VERTEBRAL COLUMN: When viewed from the anterior or posterior, a normal adult vertebral column  P a g e | 17 appears straight. But when viewed from the side, it shows four slight bends called normal curves. Relative to the front of the body, the cervical and lumbar curves are convex (bulging out); the thoracic and sacral curves are concave (cupping in). The fetus has a single anteriorly concave curve throughout the length of the entire vertebral column. At about the third month after birth, when an infant begins to hold its head erect, the anteriorly convex cervical curve develops. Later, when the child sits up, stands, and walks, the anteriorly convex lumbar curve develops. Diagram  P a g e | 18 5. BONE ANATOMY: 1. The diaphysis: is the bone’s shaft or body the long, cylindrical, main portion of the bone. 2. The epiphyses: are the proximal and distal ends of the bone. 3. The metaphysis: are the regions between the diaphysis and the epiphyses. In a growing bone, each metaphysis contains an epiphyseal (growth) plate layer of hyaline cartilage that allows the diaphysis of the bone to grow in length. 4. The articular cartilage is a thin layer of hyaline cartilage covering the part of the epiphysis where the bone forms an articulation with another bone. Articular cartilage reduces friction and absorbs shock at freely movable joints. As, the articular cartilage lacks a perichondrium and lacks blood vessels, repair of damage is limited. 5. The periosteum: is a tough connective tissue sheath and its associated blood supply that surrounds the bone surface wherever it is not covered by articular cartilage. It is composed of an outer fibrous layer of dense irregular connective tissue and an inner osteogenic layer that consists of cells. Some of the cells enable bone to grow in thickness, but not in length. The periosteum also protects the bone, assists in fracture repair, helps nourish bone tissue, and serves as an attachment point for ligaments and tendons. The periosteum is attached to the underlying bone by perforating fibres or Sharpey’s fibers, thick bundles of collagen that extend from the periosteum into the bone extracellular matrix. 6. The medullary cavity, or marrow cavity, is a hollow, cylindrical space within the diaphysis that contains fatty yellow bone marrow and numerous blood vessels in adults. This cavity minimizes the weight of the bone by reducing the dense bony material where it is least needed. The long bones’ tubular design provides maximum strength with minimum weight. 7. The endosteum: is a thin membrane that lines the medullary cavity. It contains a single layer of bone-forming cells and a small amount of connective tissue.  P a g e | 19 Diagram  P a g e | 20 FAQ: 1. What are the skeleton's primary purposes? 2. What are the different types of bones? 3. Which bone in the human body is the strongest? Why? 4. What is bone marrow, and What is the function of bone marrow? 5. Does self-healing of bone occur? If yes, then how?  P a g e | 21 PRACTICLE NO. 02 THE CIRCULATORY SYSTEM 1. HEART ANATOMY: The heart is relatively small, roughly the same size as your closed fist. It is about 12 cm (5 in.) long, 9 cm (3.5 in.) wide at its broadest point, and 6 cm (2.5 in.) thick, with an average mass of 250 g (8 oz.) in adult females and 300 g (10 oz) in adult males. The heart rests on the diaphragm, near the midline of the thoracic cavity. Recall that the midline is an imaginary vertical line that divides the body into unequal left and right sides. The heart lies in the mediastinum, an anatomical region that extends from the sternum to the vertebral column, from the first rib to the diaphragm, and between the lungs. About two-thirds of the mass of the heart lies to the left of the body’s midline. LAYERS OF HEART WALL: 1. Pericardium: The membrane that surrounds and protects the heart is the pericardium. It confines the heart to its position in the mediastinum, while allowing sufficient freedom of movement for vigorous and rapid contraction. The pericardium consists of two main parts: (1) The fibrous pericardium (2) the serous pericardium. The superficial fibrous pericardium is composed of tough, inelastic, dense irregular connective tissue. It resembles a bag that rests on and attaches to the diaphragm; its open end is fused to the connective tissues of the blood vessels entering and leaving the heart. The deeper serous pericardium is a thinner, more delicate membrane that forms a double layer around the heart. The outer parietal layer of the serous pericardium is fused to the fibrous pericardium. The inner visceral layer of the serous pericardium, which is also called the epicardium is one of the layers of the heart wall and adhere tightly to the surface of the heart. 2. Epicardium: The epicardium is composed of two tissue layers. The outermost, as you just learned, is called the visceral layer of the serous  P a g e | 22 pericardium. This thin, transparent outer layer of the heart wall is composed of mesothelium. Beneath the mesothelium is a variable layer of delicate fibroelastic tissue and adipose tissue. The adipose tissue predominates and becomes thickest over the ventricular surfaces, where it houses the major coronary and cardiac vessels of the heart. 3. Myocardium: The middle myocardium is responsible for the pumping action of the heart and is composed of cardiac muscle tissue. It makes up approximately 95% of the heart wall. The muscle fibers (cells), like those of striated skeletal muscle tissue, are wrapped and bundled with connective tissue sheaths composed of endomysium and perimysium. 4. Endocardium: The innermost endocardium is a thin layer of endothelium overlying a thin layer of connective tissue. It provides a smooth lining for the chambers of the heart and covers the valves of the heart. The smooth endothelial lining minimizes the surface friction as blood passes through the heart. CHAMBERS OF HEART: The heart has four chambers. The two superior receiving chambers are the atria, and the two inferior pumping chambers are the ventricles. On the anterior surface of each atrium is wrinkled pouch like structure called an auricle. Each auricle slightly increases the capacity of an atrium so that it can hold a greater volume of blood. On the surface of the heart are a series of grooves, called sulci that contain coronary blood vessels and a variable amount of fat. Each sulcus marks the external boundary between two chambers of the heart. The anterior interventricular sulcus is a shallow groove on the anterior surface of the heart that marks the external boundary between the right and left ventricles on the anterior aspect of the heart. 1. Right Atrium: The right atrium forms the right surface of the heart and receives blood from three veins: the superior vena cava, inferior vena cava, and coronary sinus. The right atrium is about 2–3 mm (0.08–0.12 in.) in average thickness. The anterior and posterior walls of the right atrium are very different. The inside of the posterior wall is smooth; the inside of the anterior wall is rough  P a g e | 23 due to the presence of muscular ridges called pectinate muscles which also extend into the auricle. Between the right atrium and left atrium is a thin partition called the interatrial septum. A prominent feature of this septum is an oval depression called the fossa ovalis, the remnant of the foramen ovale, an opening in the interatrial septum of the fetal heart that normally closes soon after birth. Blood passes from the right atrium into the right ventricle through a valve that is called the tricuspid valve because it consists of three layers. 2. Right Ventricle: Right Ventricle The right ventricle is about 4–5 mm (0.16–0.2 in) in average thickness and forms most of the anterior surface of the heart. The inside of the right ventricle contains a series of ridges formed by raised bundles of cardiac muscle fibers called trabeculae carneae Some of the trabeculae carneae convey part of the conduction system of the heart, in this chapter. The cusps of the tricuspid valve are connected to tendon like cords, the chordae tendineae which in turn are connected to cone-shaped trabeculae carneae called papillary muscles. Internally, the right ventricle is separated from the left ventricle by a partition called the interventricular septum. Blood passes from the right ventricle through the pulmonary valve into a large artery called the pulmonary trunk, which divides into right and left pulmonary arteries and carries blood to the lungs. 3. Left Atrium: The left atrium is about the same thickness as the right atrium and forms most of the base of the heart. It receives blood from the lungs through four pulmonary veins. Like the right atrium, the inside of the left atrium has a smooth posterior wall. Because pectinate muscles are confined to the auricle of the left atrium, the anterior wall of the left atrium also is smooth. Blood passes from the left atrium into the left ventricle through the bicuspid valve which, as its name implies, has two cusps; this is also known as Mitral valve. 4. Left Ventricle: The left ventricle is the thickest chamber of the heart, averaging 10–15 mm (0.4–0.6 in.), and forms the apex of the heart. Like the right ventricle, the left ventricle contains trabeculae carneae and has chordae tendineae that anchor the cusps of the bicuspid valve to papillary muscles. Blood passes from the left ventricle through the aortic valve (aortic semilunar valve) into the ascending aorta.  P a g e | 24 Some of the blood in the aorta flows into the coronary arteries, which branch from the ascending aorta and carry blood to the heart wall. Branches of the arch of the aorta and descending aorta carry blood throughout the body. Diagram  P a g e | 25 2. HEART CONDUCTING SYSTEM: The myocardium has its own network of blood vessels, the coronary circulation or cardiac circulation. The coronary arteries branch from the ascending aorta and encircle the heart like a crown encircles the head. While the heart is contracting, little blood flows in the coronary arteries because they are squeezed shut. When the heart relaxes, however, the high pressure of blood in the aorta propels blood through the coronary arteries, into capillaries, and then into coronary veins. 1. Coronary Arteries: Two coronary arteries, the left and right coronary arteries, branch from the ascending aorta and supply oxygenated blood to the myocardium. The left coronary artery passes inferior to the left auricle and divides into the anterior interventricular and circumflex branches. The anterior interventricular branch or left anterior descending (LAD) artery is in the anterior interventricular sulcus and supplies oxygenated blood to the walls of both ventricles. The circumflex branch lies in the coronary sulcus and distributes oxygenated blood to the walls of the left ventricle and left atrium. The posterior interventricular branch follows the posterior interventricular sulcus and supplies the walls of the two ventricles with oxygenated blood. The marginal branch beyond the coronary sulcus runs along the right margin of the heart and transports oxygenated blood to the wall of the right ventricle. Most parts of the body receive blood from branches of more than one artery, and where two or more arteries supply the same region, they usually connect. These connections, called anastomoses provide alternate routes, called collateral circulation, for blood to reach a particular organ or tissue. The myocardium contains many anastomoses that connect branches of a given coronary artery or extend between branches of different coronary arteries. They provide detours for arterial blood if a main route becomes obstructed. 2. Coronary Veins: After blood passes through the arteries of the coronary circulation, it flows into capillaries, where it delivers oxygen and nutrients to the heart muscle and collects carbon dioxide and waste, and then moves into coronary veins. Most of the deoxygenated blood from the myocardium drains into a large vascular sinus in the coronary sulcus on the posterior surface of the heart, called the coronary sinus. A vascular sinus is a thin-walled vein that has no smooth muscle to alter its diameter. The deoxygenated blood in the coronary sinus empties into the right atrium. The  P a g e | 26 principal tributaries carrying blood into the coronary sinus are the following: Great cardiac vein in the anterior interventricular sulcus, which drains the areas of the heart supplied by the left coronary artery (left and right ventricles and left atrium) Middle cardiac vein in the posterior interventricular sulcus, which drains the areas supplied by the posterior interventricular branch of the right coronary artery (left and right ventricles) Small cardiac vein in the coronary sulcus, which drains the right atrium and right ventricle Anterior cardiac veins: which drain the right ventricle and open directly into the right atrium.  P a g e | 27 Diagram  P a g e | 28 FAQ: 1. What are the circulatory system's principal constituents? 2. Which primary roles does the circulatory system play? 3. What is the difference between pulmonary and systemic circulation? 4. What are common diseases of the circulatory system? 5. How do the circulatory system and other systems interact?  P a g e | 29 PRACTICLE NO. 03 GASTRO-INTESTINAL SYSTEM Alimentary canal – It comprises of: Mouth: 1. Vestibule – Slit-like space bounded externally by lips and cheeks and internally by gums and teeth. 2. Oral cavity (Buccal cavity): Palate: Roof of the buccal cavity. Anterior part: of the p hard palate, bears transverse ridges known as rugae. Posterior part: soft palate. The hinder free part of the soft palate freely hangs down as a flap, uvula. 3. Tongue – Attached to the floor mouth by a fold called lingual frenulum. 4. Teeth 5. Pharynx (Throat): 1. Nasopharynx: Lies behind the nasal cavities, above the soft palate. The Eustachian tube (auditory tube) connects the nasopharynx with the middle ear. 2. Oropharynx – Lies behind the oral cavity. The nasopharynx and oral cavity open into the Oropharynx which is a common passage for food and air 3. Laryngopharyx – Most inferior part of the pharynx. It leads to the oesophagus behind into the larynx infront. 6. Oesophagus: Food pipe. 3 parts – Cervical part in the neck, thoracic part in the thorax and abdominal part in the abdomen. Passes through the diaphragm and opens into the stomach..7. Stomach: Lesser curvature lies on the posterior surface. The greater curvature is on the anterior side of the stomach. Greater omentum: The fold of peritoneum which attaches the stomach to  P a g e | 30 the posterior abdominal wall extends beyond the greater curvature. It stores fat. Pyloric sphincter: Guards the opening between the stomach and the duodenum and periodically permits partially digested food to leave the stomach and enter the duodenum. 8. Small intestine: 9. Large intestine: 1. Caecum and vermiform appendix Rectum: Sigmoid colon opens into the rectum. Opening of anal canal – anus. 10. Rectum: Sigmoid colon opens into the rectum. Opening of anal canal – anus. The anus has an internal anal sphincter composed of smooth muscles and an external anal sphincter comprised of striped muscle fibres.  P a g e | 31 Diagram  P a g e | 32 FAQs 1. What is the process of digestion? 2. Which are the primary roles of the GI system? 3. How is the liver involved in digestion? 4. What function does the pancreas serve? 5. What are some common gastrointestinal disorders?  P a g e | 33 PRACTICLE NO. 04 EXCRETORY SYSTEM 1. ANATOMY OF KIDNEY: EXTERNAL ANATOMY OF KIDNEYS: 1. A typical adult kidney is 10–12 cm (4–5 in.) long, 5–7 cm (2–3 in.) wide, and 3 cm (1 in.) thick—about the size of a bar of bath soap—and has a mass of 135– 150 g (4.5–5 oz). 2. The concave medial border of each kidney faces the vertebral column. 3. Near the centre of the concave border is an indentation called the renal hilum, through which the ureter emerges from the kidney along with blood vessels, lymphatic vessels, and nerves 4. Three layers of tissue surround each kidney: 1. The deep layer, the renal capsule, is a smooth, transparent sheet of dense irregular connective tissue that is continuous with the outer coat of the ureter. It serves as a barrier against trauma and helps maintain the shape of the kidney. 2. The middle layer, the adipose capsule, is a mass of fatty tissue surrounding the renal capsule. It also protects the kidney from trauma and holds it firmly in place within the abdominal cavity. 3. The superficial layer, the renal fascia, is another thin layer of dense irregular connective tissue that anchors the kidney to the surrounding structures and to the abdominal wall. On the anterior surface of the kidneys, the renal fascia is deep to the peritoneum. INTERNAL ANATOMY OF KIDNEYS: 1. A frontal section through the kidney reveals two distinct regions: a superficial, light red region called the renal cortex and a deep, darker reddish-brown inner region called the renal medulla. 2. The renal medulla consists of several cone-shaped renal pyramids. 3. The base (wider end) of each pyramid faces the renal cortex, and its apex (narrower end), called a renal papilla, points toward the renal hilum.  P a g e | 34 4. The renal cortex is the smooth-textured area extending from the renal capsule to the bases of the renal pyramids and into the spaces between them. It is divided into an outer cortical zone and an inner juxtamedullary zone. 5. Those portions of the renal cortex that extend between renal pyramids are called renal columns. 6. Together, the renal cortex and renal pyramids of the renal medulla constitute the parenchyma or functional portion of the kidney. 7. Within the parenchyma are the functional units of the kidney—about 1 million microscopic structures called nephrons. Filtrate formed by the nephrons drains into large papillary ducts, which extend through the renal papillae of the pyramids. The papillary ducts drain into cuplike structures called minor and major calyces 8. Each kidney has 8 to 18 minor calyces and 2 or 3 major calyces. 9. A minor calyx receives filtrate from the papillary ducts of one renal papilla and delivers it to a major calyx. 10. Once the filtrate enters the calyces it becomes urine because no further reabsorption can occur. 11. The reason for this is that the simple epithelium of the nephron and ducts becomes transitional epithelium in the calyces. 12. From the major calyces, urine drains into a single large cavity called the renal pelvis and then out through the ureter to the urinary bladder. 13. The hilum expands into a cavity within the kidney called the renal sinus, which contains part of the renal pelvis, the calyces, and branches of the renal blood vessels and nerves. 14. Adipose tissue helps stabilize the position of these structures in the renal sinus.  P a g e | 35 Diagram FAQs: 1. Which primary roles does the excretory system play? 2. What is the composition of urine? 3. What part does the skin play in excretion? 4. How is homeostasis maintained by the excretory system? 5. How can I maintain the health of my excretory system?  P a g e | 36 PRACTICLE NO. 05 RESPIRATORY SYSTEM 1. Conducting Zone: Made up of rigid passageways that serve to warm, moisten, and filter the inhaled air: nose, nasal cavity, pharynx, larynx, trachea, primary bronchi, tertiary bronchi, bronchioles, terminal bronchioles. Air passages undergo 23 orders of branching in the lungs which significantly increases cross sectional area for flow. 2. Respiratory Zone: Site of gas exchange: Consists of respiratory bronchioles, alveolar ducts, alveolar sacs, and about 300 million alveoli accounts for most of the lungs’ volume and provide tremendous surface area for gas exchange. The Steps Involved in Respiration: 1. Pulmonary ventilation, or breathing, is the inhalation (inflow) and exhalation (outflow) of air and involves the exchange of air between the atmosphere and the alveoli of the lungs. Inhalation permits O2 to enter the lungs and exhalation permits CO2 to leave the lungs. 2. External (pulmonary) respiration is the exchange of gases between the alveoli of the lungs and the blood in pulmonary capillaries across the respiratory membrane. In this process, pulmonary capillary blood gains O2 and loses CO2. 3. Internal (tissue) respiration is the exchange of gases between blood in systemic capillaries and tissue cells. In this step the blood loses O2 and gains CO2. Within cells, the metabolic reactions that consume O2 and give off CO2 during the production of ATP are termed cellular respiration. The organs of the respiratory system include the nose, pharynx, larynx, trachea, bronchi, and their smaller branches, and the lungs, which contain the alveoli. The organs of the respiratory system include the nose, pharynx, larynx, trachea, bronchi, and their smaller branches, and the lungs, which contain the alveoli. The Nose: The nose is the only externally visible part of the respiratory system ` Nostrils. During breathing, air enters the nose by passing through the nostrils, or nares. Nasal cavity. The interior of the nose consists of the nasal cavity, divided  P a g e | 37 by a midline nasal septum. Olfactory receptors. The olfactory receptors for the sense of smell are located in the mucosa in the slit like superior part of the nasal cavity, just beneath the ethmoid bone. Respiratory mucosa. The rest of the mucosal lining, the nasal cavity called the respiratory mucosa, rests on a rich network of thin-walled veins that warms the air as it flows past. ` Mucus. In addition, the sticky mucus produced by the mucosa’s glands moistens the air and traps incoming bacteria and other foreign debris, and lysozyme enzymes in the mucus destroy bacteria chemically. Pharynx. The pharynx is a muscular passageway about 13 cm (5 inches) long that vaguely resembles a short length of red garden hose. Function. Commonly called the throat, the pharynx serves as a common passageway for food and air. Portions of the pharynx. Air enters the superior portion, the nasopharynx, from the nasal cavity and then descends through the oropharynx and laryngopharynx to enter the larynx below. larynx The larynx or voice box routes air and food into the proper channels and plays a role in speech. Structure. Located inferior to the pharynx, it is formed by eight rigid hyaline cartilages and a spoon-shaped flap of elastic cartilage, the epiglottis. Thyroid cartilage. The largest of the hyaline cartilages is the shield- shaped thyroid cartilage, which protrudes anteriorly and is commonly called Adam’s apple. Epiglottis. Sometimes referred to as the “guardian of the airways”, the epiglottis protects the superior opening of the larynx. Vocal folds. Part of the mucous membrane of the larynx forms a pair of folds, called the vocal folds, or true vocal cords, which vibrate with expelled air and allows us to speak. Glottis. The slit like passageway between the vocal folds is the glottis. Trachea Length. Air entering the trachea or windpipe from the larynx travels down its length (10 to 12 cm or about 4 inches) to the level of the fifth thoracic vertebra, which is approximately midchest.  P a g e | 38 Structure. The trachea is fairly rigid because its walls are reinforced with C-shaped rings of hyaline cartilage; the open parts of the rings abut the esophagus and allow it to expand anteriorly when we swallow a large piece of food, while the solid portions support the trachea walls and keep it patent, or open, in spite of the pressure changes that occur during breathing. Cilia. The trachea is lined with ciliated mucosa that beat continuously and in a direction opposite to that of the incoming air as they propel mucus, loaded with dust particles and other debris away from the lungs to the throat, where it can be swallowed or spat out. Main Bronchi Structure. The right and left main (primary) bronchi are formed by the division of the trachea. Location. Each main bronchus runs obliquely before it plunges into the medial depression of the lung on its own side. Size. The right main bronchus is wider, shorter, and straighter than the left. Lungs Location. The lungs occupy the entire thoracic cavity except for the most central area, the mediastinum, which houses the heart, the great blood vessels, bronchi, esophagus, and other organs. Apex. The narrow, superior portion of each lung, the apex, is just deep to the clavicle. Base. The broad lung area resting on the diaphragm is the base. Division. Each lung is divided into lobes by fissures; the left lung has two lobes, and the right lung has three. Pleura. The surface of each lung is covered with a visceral serosa called the pulmonary, or visceral pleura and the walls of the thoracic cavity are lined by the parietal pleura. Pleural fluid. The pleural membranes produce pleural fluid, a slippery serous secretion which allows the lungs to glide easily over the thorax wall during breathing movements and causes the two pleural layers to cling together. Pleural space. The lungs are held tightly to the thorax wall, and the pleural space is more of a potential space than an actual one. Bronchioles. The smallest of the conducting passageways are the bronchioles. Alveoli. The terminal bronchioles lead to the respiratory zone structures, even smaller conduits that eventually terminate in alveoli, or air sacs.  P a g e | 39 Respiratory zone. The respiratory zone, which includes the respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli, is the only site of gas exchange. Conducting zone structure: All other respiratory passages are conducting zone structures that serve as conduits to and from the respiratory zone.Stroma. The balance of the lung tissue, its stroma, is mainly elastic connective tissue that allows the lungs to recoil passively as we exhale. The two lungs are not a mirror reflection of one another.LUNGS: 1. The right lung has three lobes; inferior, superior and middle. These lobes are further divided, giving 10 bronchopulmonary segments, which are the functional units of the lung tissue. 2. The right lung lobes are separated by two fissures; oblique and horizontal. 3. The mediastinal surface of the right lung is in contact with the heart, superior vena cava, inferior vena cava, azygos vein and the esophagus. 4. The impressions of these structures can be seen on the medial lung surface. 5. On the other hand, the left lung only has two lobes; superior and inferior, and 8 lung segments. 6. The lobes are separated by a single oblique fissure. 7. The mediastinal surface of the left lung shows impressions of the following structures: the heart, aortic arch, thoracic aorta and esophagus. 8. The lungs have two circulatory systems: functional and nutritive. The functional, or pulmonary, circulatory system is comprised of two pulmonary arteries and four pulmonary veins. 9. Pulmonary arteries originate from the pulmonary trunk, they convey deoxygenated blood from the right ventricle to the lungs. 10. By dividing into smaller vessels and ultimately into pulmonary capillaries, they reach the respiratory surfaces of the lungs. On the other hand, left and right pairs of pulmonary veins carry oxygenated blood from the lungs to the left atrium of the heart.  P a g e | 40 Diagram  P a g e | 41 FAQ 1. Which respiratory system functions are the most important? 2. What function does the diaphragm serve in respiration? 3. What interactions do the respiratory and other systems have? 4. What are common disorders of the respiratory system? 5. What can I do to maintain the health of my lungs?  P a g e | 42 PRACTICLE NO. 06 NERVOUS SYSTEM 1. FUNCTINAL AREAS OF CEREBRAL CORTEX: Specific types of sensory, motor, and integrative signals are processed in certain regions of the cerebral cortex. Generally, Sensory areas receive sensory information and are involved in perception, the conscious awareness of a sensation; Motor areas control the execution of voluntary movements; Association areas: deal with more complex integrative functions such as memory, emotions, reasoning, will, judgment, personality traits, and intelligence. 1. The Precentral (motor) area: lies in the frontal lobe immediately anterior to the central sulcus. Nerve cells and the pyramidal cells initiate the contraction of voluntary muscles. 2. The Postcentral (sensory) area (somaesthetic area): lies in the parietal lobe immediately posterior to the central sulcus. It perceives sensations of pain, temperature, pressure and touch. 3. The sensory speech area: lies in the lower part of the parietal lobe and extends into the temporal lobe. It perceives spoken words. 4. The auditory area: is positioned immediately below the lateral sulcus in the temporal lobe. It is the centre for hearing. 5. Wernicke’s area: Lies in the left temporal lobe. Its role in understanding speech and writing words. 6. The visual area: is positioned in the greater part of occipital lobe. This is the centre for sight. 7. The olfactory area: lies deep within the temporal lobe. It functions to gather knowledge about smell. 8. The taste area: It is located in the parietal lobe above the lateral sulcus in the post central (sensory) area.  P a g e | 43 9. The motor speech area / Broca’s motor speech area: is located in the frontal lobe. 10. Visual association area: is positioned in the occipital area. 11. Parietal association area: lies in the parietal lobe 12. Frontal association area: frontal lobe 13. Temporal association area: temporal lobe  P a g e | 44 Diagram  P a g e | 45 LIMBIC SYSTEM / EMOTIONAL BRAIN: The limbic system consists of: 1. Hippocampus: inside the temporal lobe 2. Amygdala / Amygdaloid nucleus: Tip of the temporal lobe 3. Septal nuclei: within the septal area formed by the regions under corpus callosum and paraterminal gyrus. 4. Mamillary bodies: behind the infundibulum 5. Basal ganglia: scattered masses of grey matter Functions: 1. Controls emotional behaviour of humans 2. Controls food habits Controls sexual behaviour  P a g e | 46 2. ANATOMY OF HUMAN BRAIN: 1. Prosencephalon: Includes olfactory lobes, cerebrum and Diencephalon 2. Mesencephalon: Includes corpora quadrigemina and crura cerebri. 3. Rhombencephalon : Includes cerebellum, pons varolli and medulla oblongata. All the above three are known as the primary brain vesicles. FOREBRAIN / PROSENCEPHALON: i. Olfactory lobes: 1. Anterior part of the brain is formed by a pair of short club-shaped structures. 2. Each lobe consists of 3. An anterior olfactory bulb and a posterior olfactory tract. 4. Fully covered by the cerebral hemisphere and hence, only visible in the ventral view of the brain. Olfactory nerves arise from the olfactory lobes. 5. It functions for the sense of smell ii. Cerebrum:  P a g e | 47 1. Largest and the most complex of all parts in the brain. 2. Left and right hemispheres present connected by a large bundle of myelinated fibres, the corpus callosum. 3. Anteriorly, corpus callosum is folded back to form the genu. 4. Posteriorly, it curves ventrically to form rounded splenium which joins a fibrous strip called fornix. Fornix is paired and is present in each hemisphere. Cerebral cortex: 1. Outer portion of cerebrum and makes up the gray matter of the cerebrum. The surface of cortex is greatly folded. 2. The upward folds – gyri; downward grooves – sulci. 3. The large concentration of medullated nerve fibres gives this tissue an opaque white appearance hence being called as white matter. 4. Lobes: The most prominent fissure, the longitudinal fissure, separates the cerebrum into right and left halves called cerebral hemispheres. 5. Within the longitudinal fissure between the cerebral hemispheres is the falx cerebri. 1. Central sulcus: Separates the frontal lobe from the parietal lobe 2. Lateral sulcus: Separates the frontal lobe from the temporal lobe 3. Parieto-occipital sulcus: Separates the parietal lobe from the occipital lobe 4. Precentral gyrus: Located immediately anterior to the central sulcus, contains the primary motor area of the cerebral cortex.  P a g e | 48 5. Postcentral gyrus: Located immediately posterior to the central sulcus, contains the primary somatosensory area of the cerebral cortex. Basal Ganglia (Basal Nuclei): 1. Deep within each cerebral hemisphere are three nuclei (masses of gray matter) that are collectively termed the basal nuclei. 2. Corpus striatum: largest nucleus in the basal nuclei, situates at the base of the cerebral hemispheres, close to the thalamus. 3. The third of the basal nuclei is the caudate nucleus, which has a large “head” connected to a smaller “tail” by a long comma-shaped “body.” 4. Together, the lentiform and caudate nuclei are known as the corpus striatum. 5. Two of the basal nuclei lie side by side, just lateral to the thalamus. They are the globus pallidus, which is closer to the thalamus, and the putamen, which is closer to the cerebral cortex. 6. Together, the globus pallidus and putamen are referred to as the lentiform (lenticular) nucleus. Functions: 1. Controlling the movements during voluntary motor activity 2. Control of reflex muscular activity 3. Control of muscle tone 4. Control of automatic associated movements 1. DIANCEPHELON: Diancephelon mainly consists of: Epithalamus, Thalamus and Hypothalamus 1. Epithalamus: thin and not formed from nervous tissue. 1. Anterior part is vascular and folded to form pineal stalk, which has a rounded pineal body at its tip. 2. Pineal body: endocrine gland, secretes melatonin. 2. Thalamus: Lies superior to the midbrain and is composed of grey matter. 3. Hypothalamus:  P a g e | 49 1. The optic chiasma is formed in front of the hypothalamus. 2. The hypophysis (pituitary gland) is directly attached to the hypothalamus by infundibulum. 2. MIDBRAIN / MESENCEPHALON: 1. Corpora quadrigemina: The upper or superior surface of midbrain has 2 pairs of rounded protrusions collectively known as corpora quadrigemina. One pair – Superior colliculi: Connected with the sense of sight. Inferior colliculi: Concerned with the sense of hearing The superior and inferior colliculi of each side are termed as corpora bigemina. 2. Cerebral peduncles (Crura cerebri): 2 bundles of fibres which lie on the inferior surface of midbrain. They relay impulses back and forth between the cerebrum, cerebellum, pons and medulla. 3. HINDBRAIN: 1. Cerebellum – 2nd largest part of human brain. 1. 2 lateral cerebellar hemispheres and central vermis present. 2. Has grey matter on the outside, comprising three layers of cells and fibres. 3. Purkinje cells: 4. Also contain golgi cells, basket cells and granule cells. 5. Cross section of cerebellar hemispheres shows a branching tree like arrangement of grey and white matter – arbor vitae. Functions: 1. Controls rapid muscular activities 2. All actions of cerebellum are involuntary but involve learning in the early stages. 2. Pons varolli:  P a g e | 50 1. Lies in front of the cerebellum below the midbrain and above the medulla oblongata. 2. Consists mainly of nerve fibres which form a pons bridge between the 2 hemispheres of cerebellum. 3. Pneumotaxic centre present in pons. Functions: 1. Relays impulses between medulla and more superior part of brain, between the hemispheres of cerebellum and between the cerebrum and cerebellum. 2. Pneumotaxic centre limits inspiration. 3. Medulla oblongata: 1. Extends from the pons varolli above and is continuous with the spinal cord below. 2. It has a very thin, nonvascular folded structure on its lower side known as posterior choroid plexus. Functions: 1. Receives and integrates signals from spinal cord and sends the resulting signals to the cerebellum and thalamus. 2. Contains centers that regulate heart rate, blood pressure, breathing, swallowing, salivation, sneezing and some involuntary actions. 3. They connect the forebrain and spinal cord. Ventricles of brain: These are 4 hollow, fluid filled spaces inside the brain. 1. Lateral ventricle: lies inside each hemisphere of cerebrum. Each lateral ventricle is connected to the third ventricle by an interventricular foramen (Foramen of Monro). 2. The third ventricle: a narrow channel between the hemispheres through the area of the thalamus. Connected by the cerebral aqueduct or Aqueduct of Sylvius or ither in the midbrain portion of brainstem to the 4th ventricle in pons and medulla. 3. Fourth ventricle: Continuous with the central canal of spinal cord.  P a g e | 51 Diagram  P a g e | 52 3. CRANIAL NERVES: The cranial nerves pass through various foramina (openings) in the cranial bones. There are total 12 pairs of cranial nerves present in a human being. 1. Olfactory Nerve: Arise in the olfactory epithelium of the nasal chamber. It enters the olfactory bulb of the olfactory lobes found in the brain. From there, they run through the olfactory tract and lastly reach the temporal lobe of the cerebrum. Sensory nerve: carries impulses of smell from the olfactory epithelium to the brain. 2. Optic Nerve: Originate in the retina of eye and combine to form the optic nerve. 2 optic nerves meet at the floor of diencephalon where they appear to be cross to opposite side and X-shaped structure. Hence called Optic Chiasma. Sensory nerve: Carries impulses of sight from the retina to the brain.  P a g e | 53 3. Occulomotor Nerve: Arises from the floor of midbrain/ Mesencephalon. It is also called the eye mover as it supplies 4 of the 6 extrinsic eye muscles that move the eyeball in the orbit. It innervates 4 eye muscles viz. – 1. Inferior oblique 2. Superior rectus 3. Inferior rectus 4. Medial rectus Motor nerve: Carries impulses from the brain to the above muscles for controlling the movements of eyeball. Accessory occulomotor nuclei provide motor control to the smooth muscles that regulate constriction of the pupil and changes in shape of the lens via the occulomotor nerves. Attached to forebrain / Prosencephalon Attached to Midbrain / Mesencephalon 4. Trochlear Nerve: Arises from the floor of the midbrain. It supplies nerve fibres to the superior oblique eye muscle. Trochlear nerve: Thinnest and smallest cranial nerve It innervates this muscle that loops a pulley shaped ligament in the orbit.. Motor nerve: Helps in controlling the movement of the eyeball. Nuclei in the midbrain provide motor impulses that control movements of the eyeball via the trochlear nerves. 5. Trigeminal nerve: Arises from the ventral surface of the pons varolli. Largest cranial nerve. Nuclei in the pons receive sensory impulses for somatic sensations from the head and face and provide motor impulses that govern chewing via the trigeminal nerves. It bears a trigeminal (Gasserian) ganglion at its origin and divides into 3 branches 1. Ophthalmic nerve: Smallest branch of the trigeminal nerve. It runs forward through the eye orbits and innervates the lacrimal glands, the conjunctiva, the forehead, eyelids, etc.  P a g e | 54 2. Sensory nerve: Carries impulses of touch from the above mentioned areas to the brain. 3. Maxillary nerve: It innervates the cheeks, upper gums, upper teeth and lower eyelids. Sensory branch: Carries stimuli from these areas. 4. Mandibular nerve: It distributes nerve fibres to the teeth and the gums of the lower jaw, the pinna of the ear, lower lip and the tongue. Largest branch of trigeminal nerve. Mixed branch having sensory and motor fibres that help in controlling these particular organs. 6. Abducens nerve: Originates from the pons varolli. It controls the extrinsic eye muscle that abducts the eyeball and turns it laterally. It innervates the lateral rectus muscle of the eyeball. Motor nerve: Controls the movement of the eyeball. Nuclei in the pons provide motor impulses that control eyeball movement via the abducens nerves. 7. Facial nerve: Originates from the lower part of the pons varolli. It bears geniculate ganglion. It innervates the taste buds of the tongue and muscles of the face. It also innervates the salivary glands. It is a mixed cranial nerve. The sensory portion of the facial nerve also contains axons from skin in the ear canal that relay touch, pain, and thermal sensations. Axons of branchial attached to pons varolli motor neurons arise from a nucleus in the pons and exit the stylomastoid foramen to innervate middle ear, facial, scalp, and neck muscles. Nerve impulses propagating along these axons cause contraction of the muscles of facial expression plus the stylohyoid muscle, the posterior belly of the digastric muscle, and the stapedius muscle. Axons of the parasympathetic motor neurons run in branches of the facial nerve and end in two ganglia: the pterygopalatine ganglion and the submandibular ganglion.  P a g e | 55 8. Vestibulocochlear nerve / Auditory nerve: Originates from the internal ear (membranous labyrinth) and joins the lateral side of pons varolli. 1. It is a sensory nerve and is formed by two branches: 1. Vestibular nerve: Arises from the vestibular part of the membranous labyrinth (utricle, saccule and semicircular canals). Sensory nerve: Equilibrium of the body. 2. Cochlear nerve: Arises in the cochlear part of the membranous labyrinth. Sensory branch: Hearing. The nerve contains some motor fibers, but they do not innervate muscle tissue. Instead, they modulate the hair cells in the inner ear. 9. Glosso-pharyngeal nerve: Originates from the side of medulla oblongata. It innervates the taste buds, soft palate, pharynx, tongue and muscles of the pharynx. Mixed nerve: (1) Sensory axons of the glossopharyngeal nerve arise from taste buds on the posterior one-third of the tongue (2) Proprioceptors from some swallowing muscles supplied by the motor portion (3) Baroreceptors (pressure-monitoring receptors) in the carotid sinus that monitor blood pressure (4) Chemoreceptors (receptors that monitor blood levels of oxygen and carbon dioxide) in the carotid bodies near the carotid arteries and aortic bodies near the arch of the aorta, and (5) The external ear to convey touch, pain, and thermal (heat and cold) sensations. Axons of motor neurons in the glossopharyngeal nerve arise in nuclei of the medulla and exit the skull through the jugular foramen.  P a g e | 56 Branchial motor neurons innervate the stylopharyngeus muscle, which assists in swallowing, and axons of parasympathetic motor neurons stimulate the parotid gland to secrete saliva. Attached to pons varolli Attached to medulla oblongata 10. Vagus nerve: Originates from the side of medulla oblongata. It is the only cranial nerve to extend beyond the neck and head into the thorax and abdomen. Longest cranial nerve. It bears the vagus ganglion. It innervates the pharynx, larynx, oesophagus, stomach, lungs, heart and intestines. It is a mixed nerve. It controls the visceral sensations and visceral movements (peristalsis, sound production, respiratory movements, heart beats, etc). Sensory nerves: Convey sensations such as hunger, fullness, and discomfort. Motor nerves: Perform actions such as swallowing, vocalization, and coughing. 11. Accessory nerve: It originates from the brain (medulla oblongata) and spinal cord. It was originally known as spinal accessory. It is formed by the union of its cranial and spinal roots but these are associated for a short distance. Branchial motor cranial nerve: Innervates the muscles of pharynx, larynx, neck and shoulder. Controls the movements of these organs. 12. Hypoglossal nerve: Originates from the ventral side of the medulla oblongata. It innervates the muscles of tongue and hyoid apparatus.  P a g e | 57 Diagram  P a g e | 58 FAQ 1. What are neurons, and what do they do? 2. What are neurotransmitters? and enlist them. 3. What is the role of spinal cord’s and brain in the nervous system? 4. What are common disorders of the nervous system? 5. How can I keep my nervous system healthy?  P a g e | 59 Practical 7 : Blood Pressure and Pulse Rate Measurement  P a g e | 60 Setting up the Equipment 1. Sit down and open the blood pressure testing kit. Sit down at a table or desk where you can easily set up the necessary equipment. Remove the cuff, stethoscope, pressure gauge, and bulb from the kit, taking care to untangle the various tubes. 2. Raise your arm to heart level. Elevate your arm so that when you bend your elbow, your elbow is parallel to your heart. This ensures that you will not get either an overestimated or underestimated reading on your blood pressure. It is also important that your arm is supported during the reading, so make sure to rest your elbow on a stable surface. 3. Wrap the cuff around your upper arm. Most cuffs have Velcro, making it easy to secure the cuff in place. If your shirt has long or thick sleeves, roll them up first, as you can only put the cuff over very thin clothing. The bottom edge of the cuff should be about an inch above the elbow. 4. Make sure the cuff is snug, but not too tight. If the cuff is too loose, the cuff will not compress the artery correctly, giving you an inaccurately low blood pressure reading. If the cuff is too tight, it will create what is known as "cuff hypertension" and give you an inaccurately high reading. 5. Place the wide head of the stethoscope on your arm. The head of the stethoscope (also known as the diaphragm) should be placed flat against the ski on the inside of your arm. The edge of the diaphragm should be just beneath the cuff, positioned over the brachial artery. Gently put the earpieces of the stethoscope in your ears. Do not hold the head of the stethoscope with your thumb — your thumb has its own pulse and this will confuse you while you try to obtain a reading. A good method is to hold the head of the stethoscope in place with your index and middle fingers. This way, you should not hear a thumping sound until you have begun to inflate the cuff. 6. Do not hold the head of the stethoscope with your thumb — your thumb has its own pulse and this will confuse you while you try to obtain a reading. A goo method is to hold the head of the stethoscope in place with your index and middle fingers. This way, you should not hear a thumping sound until you have begun to inflate the cuff.  P a g e | 61 7. Do not hold the head of the stethoscope with your thumb — your thumb has its own pulse and this will confuse you while you try to obtain a reading. A goo method is to hold the head of the stethoscope in place with your index and middle fingers. This way, you should not hear a thumping sound until you have begun to inflate the cuff  P a g e | 62 Taking the Blood Pressure 1. Inflate the cuff. Rapidly pump the bulb to inflate the cuff. Keep pumping until the needle on the gauge reaches 180mmHg. The pressure from the cuff will occlude a large artery in the bicep, temporarily cutting off blood flow. This is why the pressure from the cuff can feel a little uncomfortable or strange. 2. Do not hold the head of the stethoscope with your thumb — your thumb has its own pulse and this will confuse you while you try to obtain a reading. A goo method is to hold the head of the stethoscope in place with your index and middle fingers. This way, you should not hear a thumping sound until you have begun to inflate the cuff. 3. Note your systolic blood pressure. As the pressure drops, use the stethoscope to listen for a thumping or knocking sound. When you hear the first thump, make a note of the pressure on the gauge. This is your systolic blood pressure. The systolic number represents the pressure your blood flow exerts on the walls of an artery after the heart beats or contracts. It is the higher number of the two blood pressure readings, and when blood pressure is written down, it appears at the top. 4. Note your diastolic blood pressure. Keep watching the gauge, while using the stethoscope to listen to the thumping noises. Eventually the hard thumping noises will turn into a "whooshing" sound. It is helpful to note this change, as it indicates that you are close to your diastolic blood pressure. As soon as the whooshing noise subsides, and you hear only silence, make a note of the pressure on the gauge. This is your diastolic blood pressure. The diastolic number represents the pressure your blood flow exerts on the wall of an artery when your heart relaxes between contractions. It is the lower number of the two blood pressure readings, and when blood pressure is written down, it appears at the bottom.  P a g e | 63 Observation Systolic Pressure Diastolic Pressure Pulse Rate :  P a g e | 64 FAQ 1. What do the blood pressure numbers mean? 2. What does pulse rate mean? 3. Why are blood pressure and pulse rate measurements important? 4. Which disorders are frequently associated with abnormal pulse rate or blood pressure? 5. How can I keep my heart rate and blood pressure in a healthy range? P a g e | 65  P a g e | 66 Practical 8 : ABO Blood group Testing Theory Blood groups are mainly determined by the presence or absence of antigens and antibodies on the surface of our red blood cells or erythrocytes. Both antigens and antibodies are the protein molecules which functions as the body’s natural defence. This is the reason blood transfusion from the wrong blood group can b life- threatening. In blood typing, we will mix the erythrocytes from an individual with known antibodies. These antibodies are raised from a monoclonal population of the B-cells that create each type of antibody - so we have separate bottle of Anti-A, Anti-B, and Anti-D antibodies (these solutions are also known as anti-sera). If the blood cells clump (agglutinate), the antibody has bound to the appropriate antigen on the cells. Your blood type matches whatever antibody caused agglutination: e.g. if your blood agglutinates in anti-B, you have the B antigen and are Type B. The groups are based on whether you have two specific antigens A and B: Group A has the A antigen and B antibody. Group B has the B antigen and the A antibody. Group AB has A and B antigens but neither A nor B antibodies. Group O doesn’t have A or B antigens but has both A and B antibodies. There’s also a third kind of antigen called the Rh factor.  P a g e | 67 Materials Required i. Toothpicks ii. Blood sample iii. Alcohol Swabs iv. Blood Lancet v. Clean glass slide vi. Sterile cotton balls vii. Biohazard disposal container viii. Monoclonal Antibodies (Anti-A, B, and D) Procedure 1. Take a clean glass slide and draw three circles on it. 2. Unpack the Monoclonal Antibodies (MAB) kit. In the first circle add Anti-A, to the second circle add Anti-B and to the third circle add Anti-D with the help of a dropper. 3. Keep the slide aside safely without disturbing. 4. Now wipe the ring finger with the alcohol swabs and rub gently near the fingertip, where the blood sample will be collected. 5. Prick the ring fingertip with the lancet and a wipe off the first drop of the blood. 6. As blood starts oozing out, allow it to fall on the three circles of the glass slide by gently pressing the fingertip. 7. Apply pressure on the site where it was pricked and to stop blood flow. Use the cotton ball if required. Mix the blood sample gently with the help of a toothpick and wait for a minute to observe the result.  P a g e | 68 Observation  P a g e | 69 FAQ 1. Why is ABO blood group testing important? 2. What is the universal donor and universal recipient blood type? 3. Can my blood type change? 4. Can blood type affect health? 5. Is it necessary to know my blood type?