1. BloodJorge Melo

2. Objectives Describe the functions and structures of red bloodcells, white blood cells, and platelets List the features that make red blood cells efficient inthe transport of oxygen List components of the blood plasma Describe the clotting process 3. Mind map The blood Blood plasma Red blood cells White blood cells Platelets 4. Introduction Main transport medium in the body. Several other functions. Defends the body against disease. Maintains diffusion gradients. 5. The Blood It transports respiratory gases to and from the alveoliand it removes absorbed food from the small intestine. It acts as a buffer. Many of the blood proteins are able to neutraliseexcess acid or alkali and so keep the pH of the bloodconstant. Pressure for such processes as the formation of tissuefluid and filtration by the kidneys. Heat distribution. 6. Blood Human body 5 dm3 (5 kg) of blood 2.5 x 1013 Red blood cells (erythrocyets) 5 x 1011 White blood cells 6 x 1012 Platelets 7. Optical microscope 8. Group activity Test you knowledge: Function 3 groupsShape What do you know about: Sketch WBCs RBCs Related disease Platelets 9. SEM 10. Blood Plasma 55% of the blood is liquid 45% is made of cells. The pale yellow liquid Kidneys regulate pH and salt concentration of the plasma Plasma contains: Plasma proteins, such as albumins (for the osmotic balance of the blood), antibodies (for immunity) clotting factors such as fibrinogen. 11. Blood Plasma Absorbed food molecules, such as glucose, amino acids and fatty acids. Excretory waste products, such as CO2, urea and uric acid. Hormones, salts and heat. 12. Blood Plasma 13. White blood cells 14. White Blood Cells Also called leucocytes and there are at least fivedifferent types. What they have in common is that they protect thebody form disease-causing organisms as part of theimmune system. Bigger than RBC but less abundant 15. White blood cells Nucleus Spherical or irregular in shape Lymphocytes (produced in the lymph): antibody production Neutrophils (made in red bone marrow): responsible for phagocytosis 16. White blood cells Phagocytosis Phagein (devour) Kitus (cell) Osis (process) phagocytes 17. White blood cells 18. Leukaemia Type of cancer (blood or bone marrow) abnormal increase of immature white blood cells called "blasts Genetic mutations 19. Leukaemia Main symptoms Lack of platelets WBC may be supressed or dysfunctional Infections Anaemia Diarrheal pneumonia 20. Red blood cells 21. Red Blood Cells RBCs are also known as erythrocytes. They transport oxygen from the lungs to the tissues. Haemoglobin which combines with oxygen to give oxyhaemoglobin. Dead RBCs are scavenged by the liver 22. Red blood cells No nucleus, more room for thehaemoglobin Biconcave shape Quite small (7 m) 120 days cycle 23. Red Blood Cells Slows down the blood flow Gas exchange more efficient Cells stay there longer 24. Red Blood Cells Packaging the haemoglobin inside red blood cells rather than dissolving it in the plasma means that the solute potential of the blood is not affected. increases the amount of oxygen that each cell can carry. 25. Red Blood Cells Large surface area : volume ratio. Lot of membrane over which gas exchange canoccur. This means that no molecule of haemoglobin is farfrom the cell surface membrane and its source ofoxygen. 26. Red Blood Cells In the embryo,red blood cells are made in the liver. This function istaken over bythe red bonemarrow soonafter birth. 27. Anaemia Most common blood disorder Decrease in RBCs Excessive blood loss Excessive blood cell destruction Deficient red blood production Low number of haemoglobin in the RBC hypoxia (lack of oxygen) 28. Sickle cell disease Genetic blood disorder Abnormal ,rigid, sickled shape Decreases flexibility 10 to 29 days life spam Bone marrow cannot make new RBCs fast enough toreplace the dying ones Block blood flow 29. Platelets 30. Platelets small cell fragments consisting of cytoplasmsurrounded by the cell surface membrane. No nucleus 3 m in diameter. made in the bone marrow last about 6 or 7 days. 31. Platelets blood clotting. Injury to the linins of ablood vessel exposescollagen fibres. The platelets stick tothese and swell, thisreleases chemicals calledthromboplastins. 32. Damaged blood vessel and plateletsThromboplastinsClotting factorsCa2+ProthrombinThrombinFibrinogenfibrin 33. Platelets These attract several plasma proteins called clottingfactors to the site of the injury. These set off a cascade effect in the presence ofcalcium ions. The inactive plasma protein prothrombin changes tothrombin. 34. Platelets Thrombin converts another plasma protein, fibrinogen, to its insoluble form, fibrin. Fibrin forms a mesh of threads, which trap the red blood cells, so helping to block the cut. These dry to form a clot, preventing entry of bacteria and further loss of blood, and allowing the wound to heal. 35. Haemophilia Hereditary genetic disorder Inability of clotting blood Bleeding X Y X-linked traitXXXXYXh XhX XhY 36. Task 2 37. Objectives Describe the functions and structures of red bloodcells, white blood cells, and platelets List the features that make red blood cells efficient inthe transport of oxygen List components of the blood plasma Describe the clotting process