BIO_103_Circulation%2C+Respiration%2C+Excretion_L12_Spring+2022.pdf
- 1. Circulation, Respiration & Excretion: At a glance
- 2. The Blood System Blood is a specialized body fluid that is composed of a liquid called blood plasma and blood cells suspended within the plasma. Blood constitute about 7% of the body's total weight (5 liters/70 kg person). The blood flows from the heart into arteries, then to capillaries, and returns to the heart through veins. Composition 52–62% liquid plasma 38–48% cells The plasma: water, 91.5% (solvent for transporting other materials) protein, 7% albumins (54%), globulins (38%), fibrinogen (7%), other stuff (1%) other stuff 1.5% Blood is slightly alkaline (pH = 7.40 ± .05) and a slightly heavier than water (density = 1.057 ± .009).
- 3. The Blood System Cells: all blood cells are manufactured by stem cells stem cells live mainly in the bone marrow formation of blood cellular components from stem cells is called hematopoiesis the stem cells produce hemocytoblasts that differentiate into the precursors for all the different types of blood cells.
- 5. The Blood System Three types of blood cells Erythrocytes, Red blood cells, RBCs Leukocytes, White blood cells, WBCs Thrombocytes, Platelets Granulocytes large granules in the cytoplasm Agranulocytes without granules Neutrophils Eosinophils Basophils Lymphocytes Monocytes T Lymphocytes B Lymphocytes
- 6. The Blood System Normal Adult Blood Cell Counts Red Blood Cells 5.0 X 106/mm3 Platelets 2.5 X 105/mm3 Leukocytes 7.3 X 103/mm3 Neutrophil 50-70% Lymphocyte 20-40% Monocyte 1-6% Eosinophil 1-3% Basophil <1%
- 7. What it carries oxygen from the lungs to the rest of the body carbon dioxide from the body to the lungs digested food from the gut to the rest of the body wastes to the kidneys hormones from the endocrine glands to where they are needed It maintains acid base balance, body temperature It protects the body by engulfing germs and forming antibodies
- 8. Blood performs many important functions within the body including: • Supply of oxygen to tissues (bound to hemoglobin which is carried in red cells) • Supply of nutrients such as glucose, amino acids and fatty acids (dissolved in the blood or bound to plasma proteins) • Removal of waste such as carbon dioxide, urea and lactic acid • Immunological functions, including circulation of white cells, and detection of foreign material by antibodies • It maintains acid base balance, body temperature. • Messenger functions, including the transport of hormones and the signaling of tissue damage. Function of Blood
- 10. Red Blood Cell Red blood cells are the most common type of blood cell and also known as RBCs, or erythrocytes. Erythrocytes consist mainly of hemoglobin, a complex molecule containing heme groups. Oxygen can easily diffuse through the red blood cell's cell membrane. The diameter of a typical human erythrocyte disk is 6–8 µm, much smaller than most other human cells.
- 11. • The process by which red blood cells are produced is called erythropoiesis. •Erythrocytes are continuously being produced in the red bone marrow of large bones, at a rate of about 2 million per second. (In the embryo, the liver is the main site of red blood cell production). In an adult, the total count of RBC is 4.5 to 5.5 million per mm3 of blood.
- 12. White Blood Cells White blood cells or leukocytes are cells of the immune system defending the body against both infectious disease and foreign materials. Leukocytes are found throughout the body, including the blood and lymphatic system. White cells called phagocytes can eat up the germs that cause diseases.
- 13. Platelets Platelets, or thrombocytes, are the cells circulating in the blood that are involved in the cellular mechanisms of primary hemostasis leading to the formation of blood clots. Dysfunction or low levels of platelets predisposes to bleeding, while high levels, although usually asymptomatic, may increase the risk of thrombosis. Like red blood cells, platelets in mammals are anuclear (no cell nucleus) and discoid (disc shaped); they measure 1.5–3.0 μm in diameter.
- 14. Figure – RBC, WBC and Platelets
- 15. Plasma Blood plasma is the liquid component of blood, in which the blood cells are suspended. It makes up about 55% of total blood volume. Blood plasma is prepared simply by spinning a tube of fresh blood in a centrifuge until the blood cells fall to the bottom of the tube. Blood serum is blood plasma without fibrinogen or the other clotting factors.
- 17. The Heart The heart acts as a pump to propel blood to all tissues of the bodies The average human heart beating at 72 BPM, will beat approximately 2.5 billion times during a lifetime of 66 years.
- 19. How the heart pumps blood: The heart is usually felt to be on the left side because the left heart (left ventricle) is stronger (it pumps to all body parts). There are two atria, one on either side of the heart. On the right side is the atrium that holds blood that needs oxygen. It sends blood to the right ventricle which sends it to the lungs for oxygen. After it comes back, it is sent to the left atrium. The blood is pumped from the left atrium and sent to the ventricle where it is sent to the aorta which takes it to the rest of the body.
- 20. In a four-chambered heart, such as that in humans, there are two ventricles: the right ventricle pumps blood into the pulmonary circulation for the lungs, and the left ventricle pumps blood into the systemic circulation for the rest of the body. Ventricles have thicker walls than the atria, and thus can withstand higher blood pressure. Comparing the left and right ventricle, the left ventricle has thicker walls because it needs to pump blood to the whole body. How the heart pumps blood: cont
- 21. Heart Disease The heart gets its own blood supply from coronary arteries. If these arteries get blocked the result is heart disease.
- 22. How can heart disease are avoided: Cutting down on fried food. We can grill, boil or steam, rather than fry. If we do fry, we should use corn, soya or sunflower oils. Eating less red meat. Cutting off any fat while eating anything Eating less dairy foods ( eggs, butter, milk and cream ) Eating more poultry and fish, because they are less fatty. Eating more fresh fruit and vegetables. No smoking. Taking exercise regularly. Taking time to relax before we go to bed.
- 23. Circulatory System The tubes that carry blood are called blood vessels. The circulatory system consists of The Heart, Blood vessels, Blood
- 24. The Circulatory system The function of the right side of the heart is to collect de- oxygenated blood, in the right atrium, from the body and pump it, via the right ventricle, into the lungs (pulmonary circulation) so that carbon dioxide can be dropped off and oxygen picked up (gas exchange). The left side collects oxygenated blood from the lungs into the left atrium. From the left atrium the blood moves to the left ventricle which pumps it out to the body. On both sides, the lower ventricles are thicker and stronger than the upper atria. The muscle wall surrounding the left ventricle is thicker than the wall surrounding the right ventricle due to the higher force needed to pump the blood through the systemic circulation.
- 25. How Blood Flows in the Body?
- 26. Lungs and gas exchange The primary function of the lungs is to provide oxygen to the tissues and remove carbon dioxide to outside. Respiration includes two phases (i) inspiration (ii) expiration Inspiration means supply of oxygen from the atmosphere to the tissue space through respiratory tract and blood. Expiration means transport of carbon dioxide from the tissue space to atmosphere through respiratory tract and blood. The respiratory system is made of (i) Lungs: gas exchanging organ (ii) Chest wall & respiratory muscle→ increase & decrease the size of the thoracic cavity (iii) Areas in the brain → control the muscles
- 27. How tissue gets oxygen and release carbon dioxide How Red Cells carry oxygen :
- 28. Excretory System Kidneys are the excretory organ of our body. These are the major component of urinary system. Urinary system includes (i) Kidneys...formation of urine (ii) Ureters…transport of urine from kidneys to urinary bladder (iii) Urinary bladder…reservoir of urine (iv) urethra...passage of urine from urinary bladder to outside
- 29. Kidney Structure Each kidney contains about one million Nephrons which are the structural & functional unit of kidneys. Figure – General organization of the kidneys and the urinary system
- 30. Functions of kidneys Excretion of excess unnecessary substances & metabolic waste products Osmoregulation Regulation of (i) water & electrolyte balances (ii) acid-base balances (iii) blood pressure (iv) red cell production Osmoregulation is the process by which cells and simple organisms maintain fluid and electrolyte balance with their surroundings.
- 31. How kidneys clean blood Kidneys clean blood by filtering it. They filter all our blood 300 times a day. The filtering is done by over a million tubes packed into each kidney. These tubes are called nephrons. Some people’s kidneys are not very good at filtering blood. Dialysis is used for peoples suffering from mal function of kidney.