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1 Anatomy and Physiology. Anatomy: This is the science that deals with the structure of the body and the relationship between its various parts. Physiology: This is the science that deals with the functioning or working of the human body. Cells: A cell is the basic and minute structure of all living organisms. It has a nucleus that is surrounded by the cytoplasm, which holds the required nourishment for the nucleus. The nutrients are: 1. Protein 2. Fat 3. Carbohydrate 4. Minerals 5. Water 6. Calcium etc. Cells grow by division and multiplication which is called ‘Mitosis’. Various cells are produced in different parts of the body e.g. • Muscle cells • Hair cells • Blood cells The growth of these cells can only be seen through a microscope. A microscope is an instrument which produces a

2 greatly enlarged image of objects that are normally invisible to the human eyes. Thousands of cells break down and reproduce themselves daily. Cells below the skin are fatty cells which are found in the sebaceous gland, which act as a lubricant moistening the skin stopping it from getting cracked etc. Some cells have a defect in their makeup called ‘Sickle cell’. The Nucleus: The nucleus is vital to the cell because it governs the nutrition growth and reproduction of the cells. It is the command centre for the cell and it directs all activities of the cell. The nucleus is composed of R.N.A which means ‘Ribonucleic Acid’. This helps to convey instructions from the nucleus to the cytoplasm. Functions of cells: 1. It can absorb nutrients and oxygen. 2. It is capable of growth and repair 3. It can excrete waste product 4. It can reproduce by division and multiplication 5. Some cells have the power of movement 6. It has the power to receive and react to stimuli such as light, heat, cold etc. The four stages of Mitosis: 1. Prophase 2. Anaphase 3. Metaphase 4. Telophase – resting stage of mitosis. Sickle Cell: This is a hereditary disease, in that the red blood cell are round, but sickle cell has a pointed end, thus when floating in the

3 plasma which is the transportation system it destroys the other cells. The cell will then move towards the oxygen. Sickle cell then moves throughout causing pain and swelling, when it meets with nerve ending under the skin. By then all the cells are destroyed and the body cannot produce any anti-bodies to fight the disease so they have to get oxygen from the oxygen cylinder. The Skeleton System: This is the bony frame work of the body, consisting of around 206 bones. These bones are joined together with very strong bonding. Cartilages are strong bonds of slightly elasticized fibrous tissue joining bones to the muscle. Ligaments: are bonds of fibrous tissue connecting bones to bones forming joints. Bones are the hardest of connective tissues. Composition of bones: Bones are 50% solid and 50% liquid. The solid is calcium and gasses, and the liquid is water and gasses. Types of Bones: There are four types of bones: 1. Long bones – bones of the arms and legs 2. Short bones – bones of the wrist and foot 3. Flat bones – bones of the skull and scapula 4. Irregular bones – bones of the vertebral column and the face. The skeleton is made up of the skull, bones of the thoracic or chest, back bone or vertebral column. The pelvis and bones of the limbs.

4 Function of bones: • It acts as a frame work • It supports the organs • It enables good posture • It enables free movement • It provides red blood cells which are manufactured in the centre of long bones which is called the bone marrow. Bones of the skull: 1. There are eight (8) bones of the skull namely: 2. 1 Frontal – bones of the forehead 3. 2 Parietal – bones forming the roof of the skull 4. 2 Temporal – bones at the side of the skull which contains the organ of hearing. 5. 1 Occipital – bones at the back of the skull 6. 1 Ethnocide – a sieve like bone separating the nasal cavity from the brain 7. 1 Sphenoid – a wedge shaped bone resembling a bat without stretch wings, which forms part of the base of the skull. Bones of the skull are joined together by a suture lining which makes them immovable. In the case of an infant the spaces is known as fontanels which full in as the bone begin to calcify or grow harder. Bones of the face: There are (14) bones of the face: • 2 Maxilla – bones which unite to form the upper jaw. • 2 Zygomatic – cheek bone • 2 Nasal – bones of the nose • 2 Lachrymals – bones of the ye • 2 Palatines – bones which forms the back portion of the nasal

5 and orbital cavity 2 Turbinate inferior – the side of the lower nose bone on the outer wall of each nostril 1 Vomer – bone in the back of the nose which separates each nostril 1 Mandible – the lower jaw. The mandible or lower jaw bone is a hinge like joint which moves from side to side. The teeth: The teeth are contained in sockets. It is the spongy parts of the upper and lower jaw. These are lined with periosteum which is attached to the teeth sockets and provides it with nourishment. Each tooth consists of a root, a crown and a neck, and it is made up of dentine, which gives shape to the tooth and encloses a pulp cavity containing nerves and blood vessels. Enamel is the hardest substance in the body caps, the crown and cement covers the root. The teeth begin to form before birth and erupted from six months onwards. There are twenty (20) teeth in the temporary set and 32 teeth in the permanent set. Bones of the scapula: The scapula is the large flat bone of the shoulder, forming a part of the shoulder girdle, articulating with the upper limbs, the thoracic cage and the sternum or breast bone. The clavicle or collar bone: This is the long bone articulating with the scapula and humorous. Bones of the Rib cage: The Rib cage is consisted of twelve pairs of arches of bones.

6 The first seven pairs are attached to the sternum or breast bone in front and to the vertebral column in the back. The next three pairs are attached to each other and to the seven in front the two floating ribs are called false ribs. They are only attached to the vertebral column in the back and are left hanging in front. The Diaphragm: The diaphragm is one of the most important muscles in the body. It separates the thoracic region from the abdominal region. When it is paralyzed, as sometimes happens in poliomyelitis, the patient has to be nursed in an iron lung to enable him to breath. It also helps in action requiring downward pressure like moving of the bowel, passing of urine and in childbirth and respiration. The chief body tissues: 1. The Epithelial tissue 2. The muscle tissue 3. The nerve tissue 4. Connective tissue 5. Bone or Osseous tissue. Bones of the upper limb: The Humorous: This is the long bone of the upper arm. This has a shaft with a rounded head at the upper extremities which articulate with the glenoid cavity of the scapula, to form a ball and socket joint. The lower end of the humorous flattened.

7 The Radius: The radius is one of the long bones of the forearm, situated on the inner or thumb side of the arm. It articulates at the elbow with the humorous. At its lower end the radius rotates round the ulna to form a pivot joint. The Ulna: The ulna is on the outer or little finger side of the forearm and it also articulates with the humorous at the elbow. The projection of the bone at the upper end of the ulna is called ‘olecranon’. Both the radius and the ulna articulate with the lower end of the humorous to form a hinge joint: • Antecubital fossa (front) • Olcranon (back) The Carpals: The carpals are eight (8) small bones arranged in two rows of four at the wrist. Each carpal bone is capable of a slight movement which is called a gliding joint. The Metacarpals: These are five (5) bones of the hands articulating at one end with the carpal and at the other end with the phalanges. The Phalanges: The phalanges are the short bones of the fingers and thumb, three in each finger and two in each thumb. These form hinge joint with each other and with the metacarpals at their lower end.

8 Bones of the Lower Limb: The Femur: The femur or hinge bone is the longest, strongest and heaviest bone in the body. Its head fits into the acetabulum and form the hip joint. The Patella: The patella or knee cap is developed in fibrous tissue forming muscles and tendons. The thigh muscle is called sesamoid bone. The Tibia: The tibia or shin bone is on the front of the lower leg. This bone has a sharp ridge or shin which since it is unprotected by muscles can be felt under the skin. The Fibula: The fibula or outer bone articulates with the tibia which is at the upper end and with the foot at the lower end. The Tarsal: The tarsal or ankle bone are bones of the foot, which consist of seven tarsal bone, the two longest being the calcanus which form the heel and the talus which with the tibia and fibula forms the ankle joint. The Metatarsal: The metatarsal are bones of the instep, there are five (5) of them. The Phalanges: The phalanges are bones of the toes. There are fourteen of them, three in each toe except the big toe which only has two.

9 Bones/Tissues in the Skeleton: Compact bone tissue: Is extremely hard and provide the outer protective shell of most of the bones of the skeleton. Cancellous bone tissue: This is spongy in formation and helps to lessen the weight of the bone. It is found underneath the compact bone layer and at the end of the long bones. Long Bones: This has a central hollow shaft enclosed at each end by a rounded portion. The shaft consists of compacted bones to give strength. The round portion has an outer layer of compact bones filled with cancellous bones for lightness in weight. The shaft contains yellow bone marrow. Red-marrow: this is found in the spaces of the long bone. Other types of bones do not contain bone marrow. All bones have an irregular saw like hedged, known as the ‘suture’, by which they are firmly locked together to form immovable joints. Sections of the body: The body is divided into four parts: • The head and neck • The thoracic cavity • The abdominal cavity • The upper and lower limbs.

10 Growth of bones: Bones grow from inner to outer until twenty years of age. After birth a special group of bone cells called osteoblast together mineral salt, especially calcium and phosphorus are laid down in the cartilage which gradually becomes hardened into bones. Bones of children contains less calcium salt, and are more elasticized than adults, therefore children have a type of fracture known as green stick fracture. Synovial fluid: This is a lubricate fluid found between joints which prevent the friction of bones, enabling free movement. A decrease of this fluid produces a condition known as arthritis. Ligaments: Ligaments are bonds of strong slightly elasticized fibrous tissue, connecting one bone to the other to form a joint. Ligaments allow movement and serve to protect the joint from dislocation and other injury. Disease of bone: Bones need calcium and exercise to maintain proper growth and formation. Calcium comes in the form of milk, cheese which should be taken in by the mother in abundance during the period of gestation. Lack of calcium results in: 1. Rickets 2. Lordosis 3. Dwarfism 4. Hypnosis 5. Acromyelitis

11 6. Osteomylitis 7. Ostetitis 8. Necrosis 9. Osteomalacia 10.Osteoporosis Vitamin B2 causes night blindness. Lack of vitamin B causes beriberi. Vitamin D deficiency is called Rickets. Rickets: This is a result of a deficiency in the amount of calcium salt in the bone. Bones become soft, curves and bends especially in the limbs. Lordosis: This is a form of spinal curvature in which there is an abdominal forward curve of the lumbar spine. Hypnosis: A posterior curvature of the spine. Osteomylitis: Inflammation of the bone. Necrosis: Death or destruction of a portion of the tissue. Osteomalacia: A disease characterized by painful softening of bones due to vitamin D deficit. There are three main factors which influence the normal

12 growth of bones in children are: 1. Sex hormone 2. Exercise 3. Calcium The interior of bones is supplied with blood vessels. These are contained in tiny spaces of bone tissue. The Vertebral column: The vertebral column consists of (33) irregular bones namely: 1. 7 cervical 2. 12 thoracic 3. 5 lumbar 4. 5 sacrum 5. 5 coccyx The vertebral or spinal column or backbone is irregular bones which articulate with each other. They are joined together by strong bonds of ligament. This is the most essential portion of the skeleton forming the background. This part of the skeleton runs from the occipital region of the head to the coccyx. Functions of the Vertebral column: 1. Supports the head. 2. It forms the background of the skeleton system. 3. The vertebral column accommodates and protects the spinal cord. 4. The vertebral column contains cerebra spinal fluid, which is a transparent thickened fluid, which has its own circulation from the ventricles of the brain to the coccyx. 5. It articulates with the ribs, keeping the column in position. 6. Retains the rotation for the head on the axis. It contains spinal

13 fluid between the spaces of the fourth and the fifth lumbar region. It is used for diagnostic purposes. Movement of various joints: 1. Flexion or bending – movement backward and forward. 2. Extension or straightening. 3. Adduction – movement towards the midline. 4. Abduction – movement away from the midline of the body or its parts. 5. Circumduction – movement of the limb in a circle. 6. External rotation – turning a part on its own axis towards the midline Blood: This is a rich red fluid circulating through the heart and its blood vessels, supplying the body with all the required nourishment, iron and oxygen and at the same time taking away all the impurities from the body and keeping the body warm. The quality of our blood depends on the diet we take in. An adequate diet, rich in iron will produce the quality of blood that is necessary for life’s daily activities. Each individual has around 8-10 pints of blood and when a certain amount of this is loosed by trauma etc. death can be the result. Our diet should be stable consisting of all its food values. Proteins, fat, carbohydrates, vitamin, water etc. This produce hemoglobin which has a very strong affinity for oxygen. Average hemoglobin count: Men – 13 - 16 Women – 11.5 – 14.5 Cells in the blood contain a substance called hemoglobin which

14 gives the blood its rich red colour. Composition of blood: Blood is composed of: 1. Plasma 2. Red blood cells/white blood cells 3. Platelets Plasma is the transportation system of all other cell. Plasma: This is a clear yellowish fluid consisting of about 90% water in which the name applied to the fluid portion of the blood which is composed of serum and fibrinogen, the material which produces clotting. When the plasma is clotted, the thinner fluid that separates from the clot is called serum. It is transportation system of the body. Red blood Cells: These are tiny bi-concave disc numbering about five million per millimeter. They contain a colour less pigment called hemoglobin, which with its iron carries oxygen to the body tissues. The red cells act as the carriers of oxygen. It contains hemoglobin which acts as the medium of interchange between the oxygen of the air the lungs and the tissues requiring it. Red blood cells are manufactured in the centre of bones called the bone marrow and are stored in the liver and spleen. Red blood cells have red pigment which gives blood its red colour. White blood cells: White cells are leucocytes which protect the body from the

15 harmful bacteria that may enter the tissue by surrounding and attempting to destroy the invasion of microorganisms. Leucocytes are different from erythrocytes in that they contain no hemoglobin and are therefore colorless and contain a well formed nucleus. There are three (3) main classes of white cells: 1. Granulocytes 2. Lymphocytes 3. Monocytes – has one nucleus and destroys bacteria in the blood. The granulocytes are formed in the bone marrow. The lymphocytes are formed predominantly in lymphoid tissue. Functions of the white blood cells: 1. Repair wounds 2. The absorption of foreign substance 3. The destruction of bacteria Platelets: These are tiny bodies concerned with clotting of the blood, when injury occurs preventing hemorrhage and giving the blood a staying ability. Platelets or thrombocytes are small spherical bodies in the blood. Blood groups: There are four main blood groups namely: AB – universal recipient receives blood from everybody and its self. A – Gets blood from itself and ‘O’. B – gets blood from itself and ‘O’. O – Universal donor gives blood to everyone.

16 Rhesus factor: Antibodies develop in some blood cells. A positive (RH+) mother and a negative (RH) father can result in the offspring being subnormal or jaundice in the offspring. It can be inherited. Jaundice is caused by the liver not straining the blood properly. Formation of blood: The life of a corpuscle is probably about three or four weeks at all events. The blood forming organs can restore the blood after extreme hemorrhage to its normal state in this time. To renew the wear and tear of muscle as well as to make good, when a wound is torn a constant manufacturing is going on in the marrow of bones in some glands and probably in the spleen. The spleen forms red blood cells as well as white blood cells after birth. Haemophilia: This is a female disease which is transmitted by the mother, only to her male offspring, causing the male child to be a bleeder, because clotting time is delayed. This is characterized by the delay or absence of the clotting mechanism of the blood. The slightest injury may be proven fatal. In an emergency or before surgery, fresh frozen plasma is given by injection and administered to the patient. Functions of the blood: 1. It gets rid of waste products 2. It keeps the body cells moist 3. It carries nourishment, iron, oxygen, warmth to all parts of the body

17 4. Loss of blood from trauma or some injury can cause shock, resulting in death. 5. It carries water to the tissues 6. It carries secretion from glands to where they are needed 7. It seals wounds by its power of clotting 8. It protects the body from infections by the white cells and antibodies. 9. It carries enzymes throughout the body N.B. An enzyme is a protein which will catalyze a biological reaction. The red blood cells act as oxygen carriers. The white corpuses have mainly a defensive action against the onset of infection. The fluid that the blood carries has various waste products such as carbonic acid, gas which is exhaled by the lungs. Urea and salt are removed by the kidneys and it distributes food stuff such as sugar and protein which is absorbed in the intestine and eliminated by various glands. It is from a general medium of communication between organs that are chemically interdependent e.g. carrying to the stomach, the materials for gastric juices to the muscles in the pancreas etc. and absorbing secretions needed for the general purpose of the body like those of the thyroid gland and the super renal gland. Clotting of blood: This occurs when blood is shed and is due to the formation of threads of fibrin, as it shrinks, squeezing out a clear, faintly straw colored fluid called serum. Coagulation of blood is the process whereby bleeding or hemorrhaging is normally arrested in the blood vessel; there is always some damage to tissue cells

18 and to blood platelets. As a result of this damage thromboplastin is released and comes in contact with the prothrombin and calcium in the blood. In the presence of thromboplastin and calcium, prothrombin is converted into thrombin which in turn interacts with fibrinogen, a protein always present in the blood to form fibrin. Fibrin consists of needle shaped crystals, which with the assistance of blood platelets forms a fine network in which the blood corpuses become enmeshed. The meshwork prevents any further bleeding. It will thus be seen that clotting or coagulation does not occur in the healthy blood vessel because there is no thromboplastin present. Blood groups: Blood A group has a higher risk of cancer in the stomach and pancreas. Men with type B are two inches taller than those with other blood groups. O blood group has a higher risk of duodenal ulcer. The circulatory system: The circulatory system consists of the heart and its blood vessels. The heart is a hollow muscular organ, situated in the left thoracic region, lying between the sternum in front and the lungs in the back. It is about the size of an individual’s fist. It weighs about 225 grams in women. It is heavier in men. The heart pumps about 8-10 pints of blood continuously. N.B. Blood vessels are elasticized channels through which blood flows. The blood Vessels: Blood vessels are elasticized channels through which blood travels. There are (3) three types namely:

19 1. Arteries 2. Veins 3. Capillaries These vessels have three coats: outer, inner and middle coat. Arteries: Arteries are vessels carrying blood away from the heart, with the exception of the pulmonary artery, which carries oxygenated blood, since they have to stretch with each beat of the heart, the walls of the arteries have a great deal of elastic tissue and three coats. As they reach the tissue the arteries give off smaller vessels called arterioles. Veins: Veins are thinner and have less elastic, but those of the limbs have valves that go all the way up, because the blood has to pass in an upward direction. The smallest veins are called venues. Capillaries: Capillaries are the smallest vessels of all and connect the arteries with the veins. They are found all over the body. The Internal structure of the heart: The heart is divided lengthwise into right and left halves by a thin wall of muscle tissue called the septum. There is no connection between the two sides. Each side contains two chambers, the upper called atrium and the lower called ventricle. The atrium opens into the ventricle, immediately below it, but the opening is guarded by a valve, which prevents the blood in the heart from flowing backwards. The valve on the right side of the heart is called the tricuspid valve. The outlet from the right

20 ventricle into the pulmonary artery is guarded by the pulmonary valve and that from the left ventricle into the aorta by the aortic valve. The (3) three coats of the heart: The three coats of the heart are: 1. The Pericardium – which is the tough outer coat of the heart? It is composed of fibers with a lining of serous membrane on its inner surface. The serous membrane secretes serous fluid which acts as a lubricant to ensure the smooth beating of the heart. 2. The Myocardium – this is the middle coat of the heart. It has a thick muscular coat that enables the heart to beat throughout life. 3. The Endocardium – this is a smooth delicate membrane lining the chambers of the heart and is folded back on its self to form the heart valves. Blood Vessels which are connected to the heart: The great blood vessels that are connected to the heart are: 1. the superior vena cava 2. The pulmonary artery 3. Four pulmonary vein, two from each lungs 4. The aorta The superior vena cava: This collects impure blood from the upper parts of the body. Both these vessels pour their blood through the tricuspid valve into the right ventricle.

21 The pulmonary artery: This carries blood from the right ventricle into the right and left lungs to be purified. The four pulmonary veins: These bring back oxygenated blood from the lungs into the left atrium from where it is pumped through the mitral valve into the left ventricle and into the aorta which opens out from the left ventricle and conveys purified blood to be circulated throughout the body. The Opening of the heart: 1. The pulmonary artery opens below the right ventricle 2. The pulmonary vein in the left atrium 3. The superior vena cava in the lower portion of the right atrium 4. The great aorta opens below the left ventricle Functions of the opening: The pulmonary artery gives off impure blood to the lungs to be purified. The superior vena cava collects impure blood from the head and neck to be purified by the lungs. The inferior vena cava collects impure blood from all the other parts of the body, taking it to the lungs to be purified. The pulmonary veins send oxygenated blood to the left atrium, through the mitral valve to the aorta, supplying the whole body with nourishment.

22 Functions of the heart: 1. To pump blood all over the body 2. To give the body iron, oxygen, nourishment, heat etc. 3. To maintain an equilibrium in the flow of blood Diseases of the heart: 1. Congestive heart failure 2. Enlarged heart 3. Heart murmur 4. Hole in the heart 5. Coronary thrombosis 6. Arteriosclerosis Signs and symptoms of heart disease: • Dyspnoea • Tiredness • Cyanosis Degenerative changes in the thyroxicosis, rheumatic fever, and ischemia (AD) heart due to old age Treatment: • Complete bed rest • Medication as ordered by doctor • Low salt diet • Surgery may be suggested • Less strenuous activities/occupation Blood supply: 1. Subclavian – shoulder 2. Carotid – head and neck

23 3. Auxiliary – axilla 4. Brachial – arm 5. Radial – palm 6. Digital – finger 7. Gastric – stomach 8. Renal – kidney 9. Iliac – pelvic 10.Tibia – foot 11.Pulmonary – lung 12.Hepatic – liver 13.Mesenteric – small intestine 14.Femoral – thigh 15.Popliteal – knee 16.Spleenic – spleen 17.Dorsalic – back 18.Ophthalmic – eyes 19.Temporal – ears 20.Maxillary – jaw Types of circulations: Coronary circulation: The coronary circulation is the means by which the heart itself receives its blood supply through the coronary artery. The coronary artery arises from the bone of the aorta and is contained in grooves on the outer wall of the heart. These arteries give off smaller branches to the heart. Coronary veins collect impure blood from the heart wall and pour it into the right atrium.

24 Systemic circulation: The systemic circulation means the circulation of blood to all parts of the body with the exception of the lungs. From the ventricle on the left side of the heart, the blood is pumped into the aorta and blood is conveyed around the body. From the tissues venous blood is connected into the veins and returned to the atrium on the right side of the heart. This completes the circuit. Pulmonary circulation: Pulmonary circulation differs in two ways: 1. The pulmonary arteries carry venous blood and the pulmonary veins carry arterial blood. 2. The blood leaving the heart flows in the opposite direction, so that in the systemic circulation it is pumped from the right side of the heart and is returned to the left side. The pulmonary vessels named differently from those in the rest of the body, because all vessels leaving the heart are arteries and those arteries entering the heart are veins, whatever type of blood they carry. How the lungs receive blood:? Blood is circulated through the lungs by pulmonary circulation. From the right ventricle venous blood is pumped through the pulmonary artery which divides into the right and left branches one to each lung, oxygenated blood is then returned to the left atrium by four pulmonary veins. The two layers of the lungs are: 1. Visual layer. 2. Parental layer and the fluid that runs between is serous fluid.

25 Circulatory system: The circulatory system or vasculatory system is divided for secretive purpose. 1. The blood circulatory system consists of the heart which acts as pumping organs and blood vessels through which the blood circulates. 2. The Lymphatic system consists of lymph nodes and lymphatic vessels in which colorless lymph flows. These two systems communicate with one another and are ultimately associated. Blood vessels: • Veins – are thin and large in shape • Arteries – are thicker and are more elasticized than veins. • Capillaries – are the smallest and join venules to veins etc. These are the blood vessels that transport blood. They vary considerably in size, but have the same structure consisting of three layers of tissues. 1. Tunica adventitia - or outer layer of the organ 2. Tunica media - or middle layer of smooth muscle and elasticized tissue 3. Tunica Intima – these are lining of the outer middle or the inner coat of tissue. Veins and venules: These are the blood vessels that transport blood and are mainly the same as the heart. The walls of the veins are thinner and large in shape, but have the same three layers of tissue. They are thinner because they have less muscle and elasticized tissue in the tunica media. When the veins are cut they collapse while the thinner main arteries are open, some veins possess valves which ensure that blood flows forward from the heart.

26 Organs of the heart: • Superiorly • Posterior • Inferiorly • Arterially • Laterally Superiority: This is the great blood vessel such as the aorta, superior vena cava, pulmonary arteries and veins. All these blood vessels are the superior organs of the heart. Posterior: This is an organ which is associated with the lungs. They contain the trachea and esophagus and the left and right bronchioles. Inferiorly: The apex rest on the central tendons. This also rest on the diaphragm. If the valve becomes diseased, the condition is called congestive heart failure (C.H.F). This may occur in middle age. The heart is divided into two halves by a wall called the septum. Each side has no communication with each other after birth. In rear cases where the pre-natal communication continues into childhood, circulation of oxygen bearing blood is transferred with and we see the ‘blue baby’ the condition is known as C.H.F. Blood circulation through the heart: Blood from which oxygen has been used up coming from all parts of the body is collected into two big veins called the

27 superior vena cava and the inferior vena cava, which empties into the right auricle. From there it is pumped into the right ventricle, which contracts and drives it into the pulmonary artery which in turn carries it to the lungs to pick up more oxygen. Oxygenated blood is then collected by four pulmonary veins which carries it to the left auricle, where there is a contraction and blood passes through the mitral valve and enters the left ventricle and from there it passes into the largest artery in the body, the aorta. This great vessel gives off many branches which eventually take the blood to all parts of the body. Both the aorta and the pulmonary artery are guarded by valves. (Valves are something like a trap door which opens in one direction only). This ensures that blood can only pass one way and is prevented from going backwards and not interfering with the circulation. The heart: Blood from which oxygen has been used up; coming from all parts of the body is collected into two big veins. The superior and inferior vena cava which empties it into the right Atrium and from there it is pumped into the right ventricle through the tricuspid valve, which contracts and drives into the pulmonary artery which in turn carries it to the lungs to pick up more oxygen. Oxygenated blood is then collected by the pulmonary vein which carries it to the left Atrium where there is a contraction and blood is passed through the mitral valve and enters the left ventricle. The valve then closes to prevent the back flow of blood. There is a contraction in the left ventricle; blood is then passed through the aortic valve. It enters the biggest arteries in the body, the aorta which distributes pure blood all over the body.

28 The five openings of the heart: 1. The pulmonary artery 2. The pulmonary vein 3. Superior vena cava 4. Inferior vena cava 5. Aorta Describe the internal structure of the heart: The heart is divided into two halves, the right and the left by a thin muscle called the septum. The tricuspid valve is on the right side and the mitral valve on the left side. The right side of the heart is more powerful than the left side. The digestive system: This is the system of the body which takes care of the food we eat, removing the nourishment from the food for proper maintenance of the body and getting rid of residual matter in the form of faeces, urine and perspiration. This alimentary system runs from the mouth to the anus. The Alimentary canal: This is a part of the digestive system. It is a muscular channel leading from the mouth to the anus, through which all food passes. It is lined throughout its length with mucus membrane. The alimentary canal is made up of the following parts: • The mouth with teeth, tongue and salivary gland. • the esophagus • The stomach • The duodenum and small intestines, the large intestine terminating in the rectum.

29 The Accessories of the Digestive organs are: • The Liver which manufactures bile. • The gall bladder in which bile is stored • The pancreas which secretes pancreatic juices Digestion and the breaking down of food in the small intestine: Food is taken in the mouth, crushed by the teeth, moistened by saliva, rolled into balls or bolus by the tongue, pushed to the back of the throat or soft pallet and swallowed by reflex action. It is then carried down the esophagus by peristalsis movement, when food reaches the stomach it is broken down. While food is being swallowed the epiglottis closes so that food does not get down the wind pipe or trachea. In the alimentary tract certain chemical substance is given off to the food we eat breaking them down into simple forms that can be absorbed into the blood and utilized by various parts of the body. Food is dealt with by the body in four stages: • Ingestion – mastication and swallowing • Digestion – the process by which food is being broken down • Absorption – to take in • Excretion - to expel residue and waste products. Ingestion: This is the taking in of food by the mouth, chewing or mastication by the teeth, rolled by the tongue into balls or bolus, moistened by saliva and swallowed by reflex action via the pharynx and esophagus. The salivary gland is activated by the smell of the food.

30 Absorption: This can occur from any part of the alimentary tract but it is dependent on the nature and substance of the food we eat, ordinary food mainly absorbed by the small intestine. The small intestine is 25ft long. Excretion: The large intestine also called the colon prepares the residue left from absorption for excretion through the anus. The large intestine is 5ft long. Peristalsis: This takes place in the alimentary system. A wave like churning pushing system goes on constantly on the food matter. This gets out all the food values whilst extracting the waste matter. N.B. ptyalin breaks down starch, it is formed in saliva. The stomach: An extended portion of the alimentary tract, a reservoir for food. It’s a ‘J’ shaped muscular organ situated below the diaphragm, in front of the diaphragm and spleen. Food goes to the stomach after leaving the esophagus. The stomach secretes gastric juices which break down the food in the stomach. Food takes two hour to be digested. Gastric juice is secreted at the site or small food and in larger amounts when food enters the stomach. Protein digestion begins in the stomach. Pepsin digestion begins in the stomach. Pepsin digests protein to peptone, hydrochloric acid converts pepsinogen to active pepsin and have little effect on emulsified fats except those of cream. N.B. The removal of any part of the intestine is called colostomy. The act of swallowing is called deglutition.

31 Fatty acids. The chief vessel entering the liver is the hepatic artery carrying oxygen and the portal vein carrying blood rich in nutrients. Leaving the liver are the hepatic veins and the hepatic duet, which carries bile to the gall bladder The Pancreas: This is one of the digestive glands. A leaf shaped gland situated behind the stomach in the abdominal region. The pancreas secretes two chemicals; internally it secretes a digestive juice which is squirted into the alimentary tract and stomach to break down starches and carbohydrates. Insulin is produced in the Islet of Langerhans the islet of lanperhans. In the pancreas which produces a special group of cells called ‘Beta Cells’. Beta cells manufacture insulin internally in the pancreas while pancreatic juices are produced externally. Pancreatic contributes to digestion of all food in the small intestine. The enzymes that are in the pancreas is called amylopsin (insulin breaks down sugar). The Liver: The liver is the largest gland found in the body. It weighs about 3-3 ½ lbs, it is located in the upper part of the abdominal cavity behind the diaphragm. It is irregular in shape and dark red in colour. It has right and left lobes made up of liver cells. Under the surface of the liver lies the gall bladder which produces a substance called bile which acts upon. The hepatic vein and artery supply the liver with blood. The liver can be used for a diagnostic purpose if death occurs, when the liver secretes bile it is done in the small intestine.

32 Functions of the liver: 1. It secretes bile 2. It manufactures iron 3. It destroys fat 4. It produces heat 5. It stores iron 6. It acts as a reservoir for blood 7. It helps to maintain a constant body temperature 8. It stores vitamins, especially A&D 9. It is used for diagnostic purposes to determine the cause of death 10.Detoxification (converts poisonous substances to harmless compounds) 11.It produces heparin, fibrinogen and prothrombin, which prevent the blood from clotting inside the body. The Salivary gland: 1. The parotid gland – it is found partly below and in front of the ears. 2. The sublingual gland – it is found under the front of the tongue. 3. The sub maxillary gland – it is found under the angles of the lower jaw. The salivary gland secretes a watery fluid called saliva, which contain the enzymes called saliva, which contains the enzymes called ptyalin. Enzymes begin digestion of cooked starchy food in the mouth by turning them into a simple sugar called maltose. Saliva also serves as moisture to moisten food in the mouth making it easier to swallow. During the action of swallowing food or fluid it is prevented from entering the air passage by a muscular contraction of the

33 pharynx which raises the soft palate and blocks the entrance into the nasopharynx. Enzymes: These are biological catalyst which alter, slow down or speed up the rate of chemical reaction. Characteristics of enzymes: 1. They are soluble 2. they are protein 3. They are organic catalyst 4. they are specific 5. They are sensitive acidity and alkalinity 6. They bring about reversible action 7. They are activated by chemical substances called Inhibitor. Types of enzymes: 1. Ptyalin - a breakdown of starch 2. Pepsin – a breakdown of protein into amino acids 3. Amylase - a breakdown of starch into a simpler sugar 4. Lipase – is a breakdown of fat into fatty acids to glycerol N.B. Digestion starts in the mouth and ends in the anus. This system takes care of food eaten removing the nutrients for proper maintenance of the body, while extracting the waste products. The large intestine is divided into the following parts: Caecum – ascending – transverse colon Descending colon – sigmoid colon Rectum – anus

34 Gastric juice produces hydrochloric acid which acts as an antibiotic. Nutrition: Nutrition is the combination of processes by which the body receives and uses food for growth, development and maintenance. The six classes of food nutrients are: 1. Fat 2. Protein 3. carbohydrates 4. Vitamins 5. Water 6. Minerals Protein: This contains carbon, oxygen, hydrogen and nitrogen. Proteins are found in meet eggs, milk, fish, cheese, nuts, peas, and beans. Protein is necessary for growth especially in the earliest years and for repairs of tissues after work. Carbohydrates: This contains carbon, hydrogen and oxygen. These are starch and sugar. They are found in bread, potatoes jam, honey, fruits especially grapes. Carbohydrates are energy producers in that they give heat and energy to the body. Fat: They are found in animal food, meat, fish, herring, salmon, milk, cream, butter, margarine oil which are known as ‘Lipid’. Before fat can be absorbed in the body, it is broken down into fatty acids and glycerol.

35 Water: This is required by the body in large quantities to produce the blood and other body fluids, and for the removal of waste products and replace all that is lost by sweat and other excretion. Water plays an important part in regulating body temperature. Mineral salts: These are found in all parts of the body. Calcium are found in dairy products such as fish, meat, and vegetables. Calcium is necessary for: • Formation of strong bones and teeth • It helps with the clotting of blood • It ensure proper functioning of the heart and nervous system • It helps in normal contraction of muscles. Phosphorus: This is required by bones, nerves and glands. It is found in dairy products, oatmeal and fish. Iron: This is found in green vegetables, liver, meats, eggs, cocoa and dried fruits. Iron is necessary for red blood corpuscles and the formation of hemoglobin. Sodium Chloride: Sodium chloride is common salt which can be found in nearly all foods. It is required by the blood and all body fluid. Vitamin: These are essential for growth and every part of the body.

36 Vitamin ‘A’: This helps to prevent infections. Lack of vitamin A causes night blindness. It is found in all dairy products, fats, liver; cod liver oil, and green vegetables. Vitamin ‘B’: This prevents ‘Neuritis’ (inflammation of the nerves). Lack of vitamin B1 causes ‘Beriberi’. Lack of vitamin B12 causes ‘Pernicious anemia’. It can be found in liver, whole grain containing yeast. Vitamin ‘C’: This prevents ‘Scurvy’. It is found in all vegetables and fruits especially oranges. Vitamin ‘D’: This prevents ‘Ricketts’. It is found in dairy products such as cod liver oil and animal fat. It is also produced by the action of the ray of the sun light on the skin. Vitamin ‘K’: This is essential for the clotting of blood. It is also found in liver and green vegetables. Vitamin ‘E’: This prevents absorption and is necessary for the proper working of the nervous system. It is found in wheat, liver, cereal, and egg yolk. “Roughage”: This is the indigestible part of the vegetable food which we

37 need. This gives bulk to the content of the bowels and so prevents constipation. Excretion of sweat: Sweat gland is a slender coil tube that is situated in the dermis. They continue as sweat ducts which open on the surface of the skin as sweat pores. Surrounding each sweat gland is a network of blood capillaries. The waste products such as water, urea, mineral salts. Carbohydrates are absorbed by the sweat gland. These substances are then secreted by the gland into the tubes and then pass out through the duct and into the pores as sweat. The Excretory system: Excretion is the removal of waste from the body. The excretory system consists of the kidney, which excretes urine. The lungs, which excrete carbon dioxide. The skin which excrete water and a little urea. The bowel which excretes faeces. The skin: The skin is the outer covering of the body and is sometimes referred to as the most extensive distributive organ. The skin has two layers: 1. The outer or the epidermis which covers and protects the body. 2. The inner layer or dermis consisting of sweat glands that opens on the surface of the epidermis. 3. The sebaceous gland secretes an oily substance called ‘Sebum’ which can be seen on the surface of the skin. Nerve endings are in the skin as well as blood with capillaries. Hair follicles from which the hair are grown. Fingers and toe nails are also grown from the dermis.

38 Functions of the skin: 1. It’s a protective coat for the body, from germs and injury. 2. It contains sebum 3. It absorbs the oil which acts as a lubricant 4. It gives origin to the hair 5. It absorbs vitamin D from the sunlight 6. It helps to regulate body temperature 7. It acts as a secreting organ, by secreting sweat 8. It prevents the loss of lymph and plasma The Dermis: The dermis consists of fibrous connective tissues. Sweat glands are found in the skin and all over the body, but are most abundant in the axillaries, the palm of your hand, the sole of your feet and on the fore head. Each gland consists of a coiled tube rolled up as a ball and then opens on the surface of the skin in the form of pores. Sweat glands contain clear colorless salty fluid. The Sebaceous Gland: The sebaceous gland is oily, greasy secreted glands. It is plentiful in the face, scalp and all hairy parts of the body. There is a duct that leads the secretion to the epidermis surface of the skin, and then opens into the hair follicles. This secretion is called Sebum. The wax gland in the ears is a modified type of sebaceous gland. Functions of the sebaceous gland: • It acts as a lubricant, keeping the hair and the skin moist. • It helps to prevent dryness and cracking of the skin. • It helps to supply heat to the skin.

39 Heat regulation of the body: The normal temperature of a healthy body is 98.6 degrees foreignheit which varies very little, whatever the surrounding of the climatic condition is like. If anything interferes seriously with the balance of the heat production and heat loss, death could be the result. The steady production of heat goes on with the normal processes of the body, view taking in food and burning it up to produce energy, movement and activity of the gland. Some heat is absorbed from the sun and fire. Heat is loosed by giving off energy, conduction and by radiation, from the skin to the surrounding as well. Evaporation of sweat accounts for a lot of heat loss during warm weather or violent exercise. Heat is also loosed during breathing out and heat loss during the dilation (opening of the skin vessels) to bring more blood to the surface to be cooled. ‘That is why we are flushed’. When we are hot in cold weather the same venues contracts to keep the heat in. The mechanism is under the control of heat regulating centre in the brain. Fever or Pyrexia during germs infection is a defense on the part of the body. Because the high temperature makes the condition exciting to the blood and tissues unfavorable for the growth of germs. Nerve Endings: These are sensory nerves under the skin. It is the source of pain, touch etc. Distribution of the blood vessels, below the vessels under the skin are small capillaries, these supply the skin with other blood circulation.

40 Urinary system: The urinary system is one of the four excretory systems of the body. The Kidneys: This is a bean shaped pair of excretory glands, lying in the posterior of the abdominal region in level with the lumbar region of the vertebral column. They are embedded in fat. The right kidney is slightly lower than the left. The renal vein and artery leaves and enters the kidney. The average weight of the kidneys is about 150 grams in males and 135 in females. Structures of the kidneys: 1. It is a pair of bean shaped gland. 2. The right kidney is surrounded by a smooth fibrous capsule embedded in fat. 3. The right kidney is lower than the left. 4. It is dark red in colour on the outer portion and paler on the inside. 5. The kidneys are divided into three portions. 6. Malphagia body 7. The first and second convoluting tubules, the blood vessels and supporting fibrous tissues. Functions of the kidney: 1. It excretes water 2. It excretes waste products of protein 3. It excretes salt 4. It excretes iron 5. It excretes toxic drugs and chemical substances, which may be harmful for the body.

41 6. It assists in regulating the reaction of blood, the glucose level either hyper or hypoglycaemia. Composition of blood: Urine, salt, water dissolves solid, ammonia. Normal urine is clear, yellow or amber in colour. Colour fluid slightly acidic with faintly aromatic odor. It depends on the fluid intake. Agents, which should not be found in urine: 1. Protein 2. Blood 3. Sugar 4. Bile in jaundice 5. Acetone in diabetes 6. Albumin Ureters: There are two tubes around 10” long leading urine from the kidneys to the bladder. The ureters have three coats: 1. A muscular coat 2. A fibrous coat 3. An inner lining. The bladder: This is a sac or reservoir or receptacle for urine when it leaves the kidneys via the ureters. It has four coats: 1. The mucus coat 2. The sub mucus coat 3. A muscular coat 4. The outer coat

42 When the bladder becomes over distended it may reach as high as it can contain. It holds around 1 pint of urine without being over distended. When it is over full it holds around 2-3 pints of urine. In females the lower end of the ureters becomes in contact with the uterus and in pregnancy of the advanced stage, the weight of the baby presses on the bladder downwards causing frequency of maturation. The muscles of the uterus undergo peristalsis contraction. The Urethra: This is a canal for the discharge of urine extending from the bladder to the outside. In the female its orifice lies in the vestibule between the vagina and the clitoris. In the male the urethra passes through the prostate gland to the penis and opens at the tip. In males it serves as the passage for semen as well as urine from the bladder to the exterior. In the female it’s around 1 ½ “long running along the side of the vagina. The Male Urethra: It is a muscular tube around 8” long running from the bladder to the penis. The Penis: This is the extended organ of reproduction in the male and apart of the urinary system. Disease of the bladder: • Cystitis – inflammation of the bladder • Hepatitis-Inflammation of the liver • C.A – cancer

43 Signs and symptoms of disease of the urinary system: 1. Edema 2. Pain 3. Frequent maturation 4. Burning maturation 5. Haemoptysis 6. Bleeding Abnormalities of maturation and difficulties: This may be due to an unaccustomed position in bed, this may be overcome by making the patient familiar with a particular position before undergoing an operation by giving a warm drinks and allow hot application over the lower abdomen if possible allow the patient to sit over the side of the bed. Increase frequency: This is the act of passing urine more often than once in four hours. This may be due to irritation treatment disease or pressure. Suppression of Urine: This occurs when the kidney fails to manufacture urine or when the uterus is blocked. Retention of urine: This is failure of the bladder to empty. Incontinence: This is failure of the bladder to retain.

44 Retention with incontinence: This is due to stretching of the muscles around the neck of the bladder as a result of the bladder becoming overfull. Urine dribbles away yet some always remain in the bladder. Enuresis: This is the incontinence of childhood. It may be due to faulty training or nervous, trouble or the child being cold in bed. Until the habit is cured, do not give the child anything to drink for sometimes before he or she goes to bed; wake the child at interval during the night. See to it that the child is well wrapped up and comfortable also seek medical advice if he or she appears ill. Never scold the child, but praise him or her when he is successfully spent a night dry. Catheterization: This is the act of which drawing urine from the bladder by means of a catheter. Catheter may be order by a doctor. 1. Before an operation on the pelvic organ. 2. In case when the patient cannot pass urine naturally, e.g. after an operation or in case of paralysis. 3. When a specimen of urine is required for bacteriological examination. As the bladder passes urine germs very easily contaminate it. The most careful thoroughly sterile precautions must be observed. Everything used must be sterile and the procedure should be carried out by a trained nurse. Three processes forms urine:

45 • Filtration • Re absorption • Secretion The respiration system: The essential point in respiration is the interference of oxygen from the atmosphere to the body tissues and carbon dioxide from the tissues to the atmosphere. During this interchange of gasses some water vapor is also excreted from the body in two phases: • External respiration • Internal or tissue respiration External Respiration: The absorption of oxygen from the air into the blood and the excretion of carbon dioxide from the blood into the air. This takes place into the lungs. Internal respiration: • This is when oxygen is transferred from the blood to the tissues of the body and at the same time giving off carbon dioxide. These changes take place through the walls of the capillaries. The respiratory system, therefore consist of the lungs and its air passages: 1. Nasal cavity 2. Pharynx 3. Larynx 4. Trachea 5. Bronchi 6. Bronchioles 7. Alveoli or air sac

46 Function of respiration: This is the removal of air in the lungs, which is achieved by the act of respiration. This has a two-way action, the breathing in of Oxygen from the atmosphere via the air way and the lungs and the breathing out of carbon dioxide. Inflammation of the pleura is called pleura is or pleurisy. Carbon dioxide controls breathing by stimulation in the blood. The act of breathing occurs about 18 times per minutes in a normal adult although it is much quicker in a baby. The carbon dioxide in the blood or the taking in of air stimulates it. This is the enlarging of the lungs (expanding) it occurs when the muscle between the ribs lift, and the diaphragm contracts and flatten. Every time this happens air rushes into the lungs and fills them. EXPIRATION: This is the expelling of air from the lungs. When all the muscles relax and the chest returns to its normal size forcing the air out of the lungs. Oxygen is being taken into the red blood corpuscles. While carbon dioxide is being given off. Air consists mainly of three gasses: Nitrogen, oxygen, carbon dioxide and some water vapor. Nitrogen is of no importance here; it is oxygen on which all living thing depend. With each breath of air, you take the blood receives about 5% oxygen and gives off 5% carbon dioxide. Water however, is not a solely waste material, because while it is in the blood stream, it stimulates the nerve centre in the brain, which controls breathing. For this reason, the nurse will sometimes see in the hospital ward, an oxygen cylinder. This may be given to a patient whose breathing is very slow and shallow. Giving this gas to the patient makes they breathe more deeply and quickly, thus enabling him to take in more of the life giving oxygen.

47 The Lungs: This is a pair of irregular shaped organ, occupying the greater portion of the thoracic cavity. They are separated from each other by the medo sternum, which contains the heart and its great vessels. The right lung has three lobes: upper - middle – and lower, while the left lung has two lobes the upper and lower. The neck is about 1” above the clavicle. The base is concave and is in level with the upper end of the diaphragm. The pulmonary artery and vein supplies blood to the lungs. The Epiglottis: This is a part of the air passage which is a muscular leaf shaped organ found at the top of the upper opening of the larynx and between the base of the tongue. During the act of swallowing the epiglottis close over the larynx to prevent food from going into the airway of the larynx. The air passage is lined with mucous membrane and ciliated epithelium. Structure of the Lungs: The lining is soft, light and spongy, filled with air sacs. If a portion of the lungs fall in water it will float, because of the air sacs it contains. The Pleura: This is a membranous covering of the lungs, having two layers. The visual layer and the parental layer. There is a fluid called serous fluid, which is manufactured in the lungs acting as a lubricant for the two layers of the lungs. Inflammation of this fluid is called Pleurisy.

48 Endocrine system: This is a system located in various parts of the body producing a substance called hormones from the various glands. These hormones throw its contents directly into the blood stream it has the power of controlling activities such as growth, character and sexual development. They are like chemical messenger carrying out certain functions. The endocrine gland has no ducts or tubes to lead their secretions out, but pour it directly into the blood stream. The Important Ductless Gland: 1. Thyroid gland 2. Parathyroid 3. Suprarenal 4. Pituitary 5. Gonads 6. Thymus 7. Pancreas 8. Pineal The Thyroid glands: This is situated in the lower portion of the neck having two lobes, one on either side of the trachea or windpipe. They receive their blood supply from the carotid artery; lack of iodine in the gland causes Goiter. Iodine controls the general rate of growth of the body and development of the mind and helps to keep the hair and skin healthy. Functions of the thyroid gland: It produces a hormone substance called thyroxin, which is rich in iodine, and it is stored in the blood. Thyroxin contains 65% of iodine, food iodine is found in sea-foods and most drinking water. Thyrotoxicosis is

49 caused by an over secretion of thyroxin, which is used up by the gland when it is produced instead of throwing its contents in the body. This is the process in which the food we eat changes into a substance which can be used up for body energy. Signs and symptoms of Thyrotoxicosis: This is an increase in the metabolic rate of heat. 1. It can cause over anxiety 2. Nervousness 3. Irritability 4. Loss of weight although appetite is good. 5. Excess sweating 6. Tremors of fingers 7. Hair loss Treatment: • Oral medication of thyroxin tablets • Surgery Under secretion of thyroxin: This produces a condition in children called ‘Cretinism Atrophy’ of the thyroid gland. The child is born looking normal and after six months the growth stops. If the mother had goiter the child can become mentally and physically retarded, very ugly in appearance, dryness of the skin and depress nose. Signs and symptoms: 1. General increase of weight 2. The skin becomes course, dry and thick 3. Loss of hair 4. Slow pulse

50 5. Defective memory 6. Constipation Treatment: Removal of the thyroid gland is the treatment for thyrotoxicosis and malignant goiter. Atrophy of the gland is of unknown origin. Parathyroid gland: This is situated in the neck close on either side of the thyroid gland and it is the size of a pea. There are four bodies, which control the metabolism of calcium in the body, when their secretions are defective. Tetany occurs. Thymus 1. In front of the heart (chest) 2. It helps in reproduction 3. It is large at birth but diminish at puberty. The Adrenal or Suprarenal gland: These have a yellowish body about an inch, which is situated on the upper end of each kidney. Function of the Suprarenal glands: • They produce a substance known as steroids; there are numeral, which equilibrium of water, electrolytes and balance of the body. • They assist in body healing; they produce a sex hormone called Gonads, which influences growth and development of sex. It also produces adrenaline, which is known as the emergency hormone because emergencies experiences often cause a sudden rage of fear, which leads to the release of adrenaline into the

51 blood. Adrenaline is produced in the Medulla, which acts upon the nervous system and comes into action in the time of stress. It secretes a substance used to increase the blood pressure in time of shock. The supernal glands make two secretions, one from the centre part of the gland called Adrenaline, which is poured out in the time of stress and prepares the body for flight by raising the blood pressure, quickening the pulse, deepening the breathing rate, tensing the body up to meet danger. There is a certain substance made by the outer part of the gland, which is concerned with the amount of salt in the blood and with the sex gland. The Pituitary gland: It is a small gland which is called the master gland. It is more or less a controlling gland. It is situated in the back of the brain. It is very important and exerts a controlling influence on the growth of bones. Another part of the secretion influences the functioning of the sex gland. Functions of the Pituitary gland: • It produces a hormone, which controls the metabolism of growth. • Over secretion of this hormone produces a condition called Gigantism in children. Under secretion: • The result is dwarfism • It results in obesity • It results in defective sexual development • It is responsible for the flow of milk after child birth The pituitary hormones are also concerned with regulating reproductive cycle e.g. the male hormone are concerned with the formation of sperms. In the female it is concerned with the

52 secretion of milk. Posterior or rear Lobe: Makes hormones which raise blood pressure, regulates the out flow of water from the kidneys and stimulates uterine and intestinal contraction. This hormone is often used in medicine. This gland is so important it has been named “The leader of the endocrine orchestra”. Gonads: This is a sex gland consist of the ovary in the female and the testicle in the male. The ova are produce by ovaries and sperm by the testes. In the female the sex gland is responsible for the controlling of menstruation and sexual activities. In the male the sex gland is responsible for the development of deep voice and the distribution of hair. All sexual activities are under the control of the pituitary gland and the thyroid gland. The testes produce testosterone and the ovaries produce progesterone estrogen. This hormone is produced at sexual maturity. Thymus: The thymus gland is a lymph gland situated in the chest in front of the heart. It is not a very important gland but it takes part in lymphocytes formation. It is large at birth then increase in size until puberty, and then it gradually diminishes. Myasthema Gravis: is weakness of muscles which affects vision, speaking, chewing and swallowing. Its functions are not quite clear but it may take part in the development of the reproductive system holding back their function until the proper age. Pineal: It is a small reddish gray gland that is shaped like a cone situated in the front of the cerebellum. The cerebellum is made

53 up of gray and white matter. It has no known function unlike the other gland but recently research depicts this gland associated with Parkinsonism. Hormones: Hormones are the chemical messengers of the body. A hormone is a substance which is secreted by one organ and carried in the circulation of the blood to some other organ or organs which it stimulates. Thus the adrenal bodies each weighing about half an ounce located on the kidneys secretes a hormone called adrenaline. This substance keeps the body toned up. In an emergency it is released into the blood stream and causes the same reaction during fear. When the symptoms of fear continue long after the cause of fear has been removed adrenaline is still circulated in the blood. Adrenaline also relieves fatigue particularly during great exertion. Getting one ‘second wind’ and fighting with the strength of despair are familiar phenomena. What is regarded as reserved strength is brought to the body by the stimulation of adrenaline released under excitement or exertion. Adrenaline does not add strength to the body available to the greatest possible extent. The Central Nervous System: The central nervous system is the most important of all the systems in the body. It works in connection with all the other systems. The activities of consciousness are situated in the brain as well as thought, memory, speech and the will to carry out important actions. The functions contribute to the personality of an individual. The nervous system may be divided into three main portions. The brain or spinal cord or central nervous system. The nerve or peripheral nervous system which forms the connection

54 between the central nervous system and the various parts of the body. Sympathetic nervous system this is a self compelling system, protecting the various parts of the body. The brain receives important sensation impulses which are stored in the mind forming the basis of memory. The Brain: The part of the central nervous system which lies in the cavity of the skull consisting of the following parts are: • The central hemisphere • Cerebrum • Mid Brain • Pons – Voroli • Medulla – oblongata • Cerebellum or Lesser Brain: This lies in the posterior portion of the skull near the occipital lobes. Below the medulla oblongata, the cerebellum controls five voluntary movements, which makes the muscles work together smoothly. It also controls the balance of the body. Cerebrum: This consists of the right and left cerebral hemisphere occupying the larger portion of the front and middle part of the brain. The larger portion consists of gray matter and cells. This part of the brain controls the seat of intelligence. This hemisphere contains ventricle spaces, which holds cerebo-spinal fluid which acts as a water cussion for the brain and spinal cord. Sometimes in fractures at the base of the skull, this fluid may escape through the ears.

55 Cerebrum Fracture: The function of the cerebrum is to control the movements of all the muscles of the head, limbs and trunk. It is the seat of intellect, memory, reasoning, thoughts and emotions. It is by this means that we appreciate all sensations pleasant or painful. Brain Stem: This consists of three portions: • Mid Brain • Pons • Medulla Oblongata Mid Brain: This joins to the cerebral hemisphere above and the puns below. Pons: This is found below the mid brain which articulates with the medulla oblongata below, having white and gray matters. There is a bridge of fibers which joins together all the parts of the brain. Medulla Oblongata: It is 1” long which is at the end of the brain which crosses at the back of the neck. It articulates with the brain and spinal cord. Although in a humble position possible for its protection, it is of supreme importance because it contains the vital centre of life which preserves the functions of the heart beat, circulation, breathing, swallowing and vomiting. Foramen Magnum: This is an opening in the occipital region for the entrance of the spinal cord when it leaves the brain. It lies at the back of the skull between the medulla oblongata. A patient suffering from Psychiatric disorders is experiencing

56 deterioration in the quality of the central nervous system. Near the nerve cells the brain experience great stress which could be due to trauma, genetic factors etc. Meninges: The covering of the brain and spinal cord is called meninges, which is lubricated by cerebra spinal fluid. The Meninges has three coverings: • Maters: This is the nearest to the brain it has a spongy fibrous membrane. The pia maters supply the brain with nourishment. • Dura Maters: it lines the skull, brain and spinal cord. • Arachnoids Maters: This is delicate transparent maters enveloping the brain and spinal cord. It lies between the Pia and Dura maters. Meningitis: This is inflammation of the covering of the brain. This condition causes the several of the brain to stick together causing severe pain. The most common types of meningitis are: • Meningococcal meningitis • Virus meningitis • Syphilitics’ meningitis Signs and symptoms of meningitis: • Patient is very weak • High body temperature • Vomiting • Drowsiness and sometimes delusions • Convulsions • Rigidity of the neck • Kerning sign

57 Encephalomyelitis: This is inflammation of the brain cells and spinal cord. This may arise from several causes e.g. As a complication of certain infections, especially measles and whooping cough. The spinal cord is cylinder in shape and 17” long, 2” in diameter. Spread of infection: Infection arises in two ways: • Via the respiratory tract • Via the digestive system as the virus will be found in faeces. Poliomyelitis or Infantile: Paralysis: An acute infectious disease. The virus attacks the spinal cord cells and muscles. Encephalitis: This is caused by the poliomyelitis virus. Polio encephalitis occurs mostly in the epidermis. Hydrocephalus: This is an impairment of the brain in its in-ability to articulate he cerebra-spinal fluid in the ventricle of the brain. Cranial Nerves: There are (12) twelve pairs of cranial nerves and (31) thirty-one pairs of spinal nerves. The cranial nerves branch from the stem, some are sensory bringing impulses from the brain while there are a few which both sensory are and motor fibers. 1. The olfactory nerve 2. The optic nerve

58 3. The aculo motor 4. The trachlear 5. The triangeminal 6. The abducent 7. The facial nerve 8. The auditory nerve 9. The glassoptearynxgeal 10.The vagus organs of respiration 11.The accessory nerve muscles of the shoulder/pharynx 12.Hypoglossal (Any point at which nerves are joined are called “Plexus”) Spinal nerves: There are (31) thirty-one pairs of spinal nerves branching off the spinal cord having anterior and posterior roots, uniting to form the main nerve trunk, as it leaves the vertebral column. At least two roots join together leaving the spinal cord. (They are Plexus) The Cervical Plexus: Coming from the four cervical nerves or the upper portion of the neck supplying nerves to the head and neck and skin. Brachial Plexus: This is formed from the lower cervical nerve tissues coming from the lower deeper part of the neck. They also supply the axilla, elbow, the deltoid muscle in the upper arm, the radius, ulna and phalanges. Thoracic Plexus: Running from the (12) twelve thoracic vertebral to the (4) four and (12) intercostals muscles, the abdominal walls, then to the skin of the thoracic and abdomen.

59 Lumbar Sacral Plexus: Are formed by the lumbar and sacral nerve root give branches to the back of the abdomen the sacrum femur, the legs then the sciatic nerve. Sciatic Nerve: This is the largest nerve in the body, a branch of the lumbar sacral plexus. Running from the sacrum to the pelvic to the buttocks to the back of the knee (the popliteal space) then the fibula and fibula of the leg muscles to the calf then to the muscles of the sole of the feet, to the phalanges then to the skin. Sciatica: This is inflammation of the sciatic nerve. The patient complains of pain in the thigh passes to the leg, to the ankle, this could be due to wrong site for injection etc. Lymphatic system: This is one of the systems of the body like the white cell which invades bacteria when they enter the body. This system has circulation of its own, running between the lymph, the blood, the tissues and back again; repeating this method constantly and at the same time getting rid of body impurities. Lymph is colorless. Fluid derived from the blood. There are various lymph glands situated in several parts of the body. 1. Cervical lymph gland 2. Thoracic lymph gland 3. Auxiliary lymph gland 4. Eiliac lymph gland 5. Portal lymph gland

60 The thoracic lymph gland: This is around 12” long, the tonsils, the adenoids, and the vermiform appendix at the end of the intestine. These are all lymph glands which at times when fighting against infections invading the body, they themselves go under severe pressure, becomes infected it has to be surgically removed. At times when infection invades the body, the lymph gland nearest to the infected area becomes enlarged, feverish and painful with red streaks running from the infected area to the nearest lymph gland e.g. 1. An infected toe will have its lymph gland in the groin manifesting itself. 2. An infected finger will have its lymph gland in the axilla, manifesting itself. 3. The lymph in the intestine which acts upon fat is called chyle. Having a whitish milky look. Removal of this does not endanger life. 4. Lymphocytes are formed in the lymph nodules. Functions of lymph: This helps to transport digested food and oxygen from the blood, capillaries to the cells of the body. The waste products from in the cells such as urea and carbon dioxide are absorbed by lymph and transported to the capillaries. The Spleen: The spleen is the largest lymphatic gland of all. It lies in the left of the stomach and is about 5” long. It forms the white blood cells destroying worn out red cells and store their iron. It always contains a large amount of blood, which it can send out into the circulation in emergency. Muscles: Muscles consist of a number of fibrous tissues placed side to side, running in the same direction bound together by a

61 thin membrane of connective tissues, giving the body the power of movement. The joints and muscles move upon the skeleton system. The contraction of muscles produces movements. Muscles are important because they bring about the movement in the living body due to their contraction and relaxation. When the muscle contracts it becomes shorter and when it relaxes it lengthens and becomes thinner. Muscles are effectors, meaning they respond directly or indirectly to stimulus. These are initiated, controlled and coordinated by the brain and central nervous system. They respond when they receive impulses from the nerves. Muscles are attached to bones by tendons. Voluntary Muscles: These are under the control of will. It has the power of contracting and this causes movement of the body. Voluntary muscles are those attached to the skeleton such as the arm and leg muscles. Voluntary are striped or straighten when viewed under a microscope. These muscles are under the control of will and enable the body to move freely. They are supplied with nerves from the brain and spinal cord to form muscles. Voluntary muscles work in opposition to allow the movement of flexion and extension. Involuntary muscles: These are not under the control of the will, it is found in the internal organs such as the stomach, intestine, bladder, blood vessels and bronchi. Involuntary are plain or unstrapped muscles. Cardiac Muscle: The cardiac muscle is muscle of the heart; it is a special involuntary kind of muscle that, although not under

62 will, is a special automatic rhythmic contraction which occurs without the help of the nerves supplying tissues found only in the heart walls. It enables the heart to beat continuously throughout life. Muscle tone: Even when muscles appear to be at rest it is always partially contracted and therefore ready for movement action. This state of partial contraction is called muscle tone. If a muscle lost its tone it would be compelled to take up a slack portion on the receiving stimulus which would result in delayed and inefficient movement. Smooth involuntary muscles retain its tone when all connections with the central nervous system have been severe. Chief Voluntary Muscles: 1. Epi-cranial muscle covering the cranium. 2. Facial muscle which gives expression. 3. Stern mastoid muscle – one on each side of the neck 4. Deltoid – covering the top of the shoulder 5. Trapezium – muscle covering the shoulder blade, and the back of the neck. 6. Biceps and triceps of the upper arm 7. Pectoral – are muscles over the chest 8. Intercostals muscle – lying between the ribs controlling movement 9. Latissimus dorsi- the great muscle of the middle of the back. 10.Gluteal muscle – forming the buttocks 11.Five (5) great muscle forming the abdominal wall. 12.Sartorius and quadriceps – muscle covering the of the thigh

63 13.Hamstring – at the back of the thigh 14.Gastronomes – forming the calf muscle at the back of the lower leg. Tibia muscle is over the front of the lower leg. As a result of the nerve stimulation muscles have the power of contraction and then relaxation again. The energy which enables them to perform work e.g. to contract is derived from the burning up in the body, of food stuff mainly carbohydrates from which it gets glucose, the fuel of the body. Glucose is conveyed by the blood to the muscle when it is converted into another form of starch known as glycogen and store as such until it is required during excretion. Fatigue is due to the using up of the stored glycogen and the accumulation of an acid which causes an aching sensation until muscles are rested. Rigor Mortis: This is when death occurs; the protein in the muscle gradually coagulates. The muscles loose its elasticity and become rigid. This process takes (2 hours) the muscles becomes not only rigid but stiff, therefore a corpse must be put in an acceptable position immediately after death. After rigor mortis sets in limbs have to be broken to fit in the coffin. 1. Protractor Muscle – Pull the base of the limb back 2. Retractor Muscle – Pull the limbs inward towards the body. 3. Abductors Muscle – Pull the limb outwards away from the body. 4. Rotator – Swivel the whole or part of the limb at one of the joint. 5. Flexor – Pull two parts of the limb away. 6. Extensor – Pull two part of the limbs away from each other e.g. they open joints.

64 Senses: The average person thinks of himself as possessing (5) five senses: touch, sight, taste, smell and hearing. There are at least (6) six other physiological senses: temperature (heat and cold), pain, hunger, thirst, balance or equilibrium and the muscle sense. The stimuli causing these sensations are received and carried by the nervous system of the body. The temperature sense is distributed over the whole skin of the body and also in the mucous membranes of the mouth and the passage to the pharynx. In the pharynx it is the upper part of the alimentary canal and in the opening of the nostrils the centre which receive sensations of heat, such sensations of heat and cold are perceptible only when they represent sudden change in the temperature stimuli of the body. This may be deceptive as when we touch a piece of iron we have sensation of cold, not because the iron is any colder than other objects with which we are in contact but because iron conducts heat rapidly away from the skin. Interchanges in the body may also cause heat or cold sensations as when we have a chill or a fever and sometimes we cannot tell whether the stimuli is from within or without. The brain associates the sensations it receives not with the area of the brain which are stimulated but with the ends of the nerve which bring the stimuli to the brain. Every sensation is thus referred to the region of the body in which it arises with the exception of the “external” senses of sight and sound when the sensation is referred to the object which causes it no matter how far away it may be from the body. If a nerve is stimulated mid-way of its length the stimuli is still referred to its ends. It is for a reason that a man with an artificial leg appears to have sensations in the limbs which have been amputated for the stump of his leg contains the stump of the nerve trunks which led to the leg and if

65 they are stimulated his brain refers to the stimuli to the end of the nerves even though they are not there. The senses wonderful has they are, are imperfect. We can always believe our senses as we sometimes explain for they are stimulated in which we cannot always judge accurately. A sensation of light may be caused by pressure on the eyes that is why you see ‘stars’ after a hard blow on the head. Optical illusions are familiar to everyone, since there are corresponding illusions of the outer senses, we can never be sure that what our senses tells us about the sensation of our bodies is completely indicative of a condition in the world outside of us. The Ear: This is a very complicated mechanism with which we hear an amazing variety of sounds. If you could see one of your ears in cross section (that is sliced through the middle of the parts rendering visible the inside) you would notice that the opening of the external ears leads into a passage which goes to the Tympanum or eardrum. The drum membrane is so constructed that it will respond to a range of sounds of vibrations varying from 60-4,000 vibrations per second (and to an even wider range in people with exceptionally good hearing). These vibrations are transmitted to a series of inter-articulated small bones called (from their shape) by the quaint names the hammer (malleus) the anvil (incus) and the stirrups (stapes). These bones are so arranged, that in turn they transmit the sound vibrations (with diminished amplitude but increased power) to the internal ear, in which vibrations are set up in a fluid which affects the ends of auditory nerve fibers and causes in the brain, the sensation we know as sound.

66 The ear can also distinguish loudness (intensity of sound) in various degrees, pitch and tone, quality (the timbre as for e.g. the difference which exists between the notes of a violin). The large part of the ear is truly marvelous for it has been variously estimated that the normal ear can distinguish from 6,000 to 11,000 different tones. The art of music depends on the nice distinction of which the human ear is capable. The ear pressure on both side inner as well as the outer eardrum (tympanum) is equalized by means of the Eustachian tubes, one from each ear, leading into the pharynx (back of the mouth). When a person swallows, he opens these tubes and if the barometric pressure (of the atmosphere) has changed, the swallowing permit equalization on the inner side of the tympanum in the cavity of the middle ear. The pain in the ears which sometimes accompanies ascending high mountains or going down into deep mines maybe relieved by frequent swallowing. The Eyes: The eyes include the eyeball and its appendages. The eyeball is nearly the same size in all person’s appearance, different in the size of the eyes is due to a difference in the distance between the angles of the eye lids from end to end of the visible portion of the eyeball. The eye socket (orbit) is a cavity filled with the muscles which move the eyeball, blood vessels to supply nourishment, nerves and cushions of fat. The eyeball rotates or moves in the socket pulled about by suitable muscles. It is protected in front by the eyelids of which the upper lids are the more movable being able to cover the entire eyeball in front.

67 The eyes are said to be closed (as in sleep, to protect the eye and also to prevent distraction by visible phenomena). When the upper eyelid is shut down over the eyeball. The inner side of the eye lids are covered with mucous membrane (the conjunctiva), which also covers the front of the eyeball. The edges of the eyelids are moved with hairs (eyelashes) which help to keep out flying particles of dust. Whenever there are hairs there are sebaceous glands which secrete a fatty substance to soften and lubricate the hair and skin. The edges of the eyelids are equipped with such glands. When this secretion is excessive a yellowish matter (hard and dried) occurs along the eyelids after a night sleep, sometimes even being abundant, enough to stick the lids together momentarily. The lachrymal or tear-producing apparatus is in the eye. The lachrymal or tear gland plies moisture which keeps the eyeball wet. Under emotional stress as when one cries, the tears are produced in abundant quantity and sometimes overflow down the cheeks. Usually, however the tears are carried off by the lachrymal canals which open by a pore which can be seen by a mirror in either of your eyes. If you pull down the inner corner of the lower lid slightly. Tears carried off into the nose in this way run into the pharynx and are swallowed. This causes the gulping that accompanies prolonged weeping. The act of blinking keeps the moisture from the lachrymal glands evenly distributed over the eyeball Wiping off accumulated dusts, washing it clear several times a minute.

68 The muscles of the eye attached to the back of the eyeball in the orbit, are so arrange that they can move the eye from side to side or up and down or obliquely or rotate them at will. These movements increase the range of vision which is further amplified by turning of the head. The two eyes are kept in alignment moving simultaneously by a nice adjustment of muscles and nerves. If this adjustment is impaired the condition known as squinting and (cross eye) ensues. The eye itself is the shape of a globe and nearly spherical in its main part being one inch from side to side and nine tenths of an inch from front to back. The eye ball is protected by three coats of tissue the outer is the sclerotic of which the transparent part in front of the pupil and iris is the cornea, the sclerotic where visible, is white forming the ‘white of the eye’. The second coat includes the iris which is the visible colored portion of the eye in its centre is the aperture through which to see, called the pupil, which looks black. The ring of muscle in the iris permits the contracting or narrowing of the pupil; the pupil is smallest in bright light than in diffused light. The colour of the eyes is due to the pigment in the iris. This pigment is always of lighter or darker yellow colour forming what we ordinarily call black eye, brown eye or gray eyes, depending on its intensity. Blue eyes occur when this same pigment is more deeply embedded, the blue colour being formed by the absorption of light in the outer portion of the iris.

69 The third coat of the eyeball is on the inner and rear side of the eyeball; it is called the retina. Its complex structure of blood vessels and nerve cells is the apparatus which receives the stimuli of light rays entering the eyeball through the cornea and the lens behind it. The eye is constructed somewhat like a small camera, with the shutter perpetually open (during waking hours) having a lens that can be automatically adjusted for nearer and further distances. In front of the lens (called the crystalline lens) is a space filled with transparent aqueous humor (watery fluid) behind it is the great inner globe of the eye which is filled with vitreous (jelly like) humor which is also transparent. The lens acts somewhat like an artificial glass lens to focus on the sensitive retina the rays of light passing through the cornea and pupil.

70 NOTES