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32 Cards in this Set
- Front
- Back
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Name 3 Distribution Functions of Blood?
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-Delivering oxygen from lungs and nutrients from digestive tract.
-Transporting metabolic waste from cells to elimination sites ( lungs to get rid of CO2 and kidneys to dispose of nitrogenous waste in urine)
-Transporting hormones from glands to target organs
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Name 3 regulartory functions of blood? |
- Maintaing appropriate body temp (absorbing and distributing heat, skin surface for heat loss)
-Maintaining normal ph in body tissues
-Maintaining adequate fluid volume. Blood proteins prevent excessive fluid loss into tissue. |
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Name 3 protective functions of blood? |
-Preventing blood loss- platelets and plasma protein initiate clot formation.
-Preventing infection. white blood cells |
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What percentage is of blood is erythrocytes? buffy coat? plasma? |
- 45% -<1% -55%
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What proteins are in plasma? |
60% Albumin
36%Globulins: -alpha & beta- transport proteins bind to lipids, metal ions and fat soluble vitamins -Gamma-antibodies released during immune response
4% Fibrinogen: forms fibrin threads of blood clot |
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What are the main constituents of plasma? |
-Water -Electrolytes -Proteins -Non protein nitrogenous substances -Nutrients -Respiratory gases -Hormones |
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How many litres of blood in healthy male? Female?
What percentage of body weight is blood? |
-5-6L -4-5L
-8% |
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What is the name of red blood cell production? How many days does RBC live? How are RBC made? |
-Hematopoesis -120 -Hematopoetic stem cells in bone marrow continuously divide. |
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Name 5 characteristics of erythrocytes? |
-bioconcave -no nucleus or organelles -contain hemoglobin -generate ATP by anaerobic mechanisms -picks up oxygen in capillaries of lungs and releases to tissue cells across other capillaries in body.
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What is the function and composition of the protein hemoglobin? |
Binds easily and reversibly with oxygen.
-globin- 2 alpha and 2 beta polypeptide chains and four heme groups. Each heme group has iron atom in centre. One haemoglobin molecule can carry 4 molecules of oxygen as each iron can can reversibly combine with one molecule of oxygen. |
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A single blood cell contains . . . . … .. . .. . .. |
250 million hemoglobin. |
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When oxygens binds to iron the hemoglobin is now called…….?
When oxygen detaches from iron it is now called….. ?? |
-oxyhemoglobin
-deoxyhemoglobin
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What is Carbminohemoglobin? |
20% of CO2 transported in blood binds to globins amino acids rather then heme group. |
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What glycol protein stimulates formation of erythrocytes? What do the kidneys have to do with erthropoietin? |
-Erythropoietin
-When hypoxia inducible factor accumulates, it accelerates synthesis and release of erythropoietin. |
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A drop in normal blood oxygen levels that triggers EPO formation can result from…..? |
- reduced numbers of RBCS due to haemorrhage - iron deficiency - reduced availability of oxygen ( high altitude) |
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What controls rate of erythropoiesis? |
It is not the number of erythrocytes in blood that controls rate of erythropoiesis but there ability to transport oxygen to meet demand. |
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Name 3 facts on bodies iron supply |
-65% of bodies iron supply is in hemoglobin
-Free iron ions are toxic so iron is stored inside cells in protein iron complexes such as ferritin and hemosiderin
-In blood iron is transported in protein transferrin and developing erythrocytes take up iron as needed to form haemoglobin
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Explain 5 step erythropoieitin mechanism |
1. hypoxia (inadequate 02 supply)
2. Kidneys ( and liver to smaller extent) release erythropoietin
3. Erythropoietin stimulates red bone marrow
4. enhanced erythropoiesis increases red blood cell count
5. O2 carrying ability rises |
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Never let monkeys eat bananas |
Neutrophils, lymphocytes, monocytes, eosinophils, basophils |
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Name 3 granulocytes and there function? |
-Neutrophils- most numerous-50-60% of WBC, bacteria slayers, extreme phagocytes. Respiratory burst- cells metabolise oxygen making potent germ killing oxidising substances such as belch and hydrogen peroxide.
-Eosinophils-2-4% of WBC, release enzymes which digest parasitic worms.
-Basophils-rarest- release histamine- vasodilator of blood vessels and attract other WBC to site
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What is leukopoiesis? |
Production of white blood cells stimulated by chemical messengers: interleukins or colony stimulating factors. |
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Name 2 granulocytes? |
-Lymphocytes- T AND B cancer killing
-Monocytes- Macrophages- phagocytic |
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What is the difference between Leukemia and leukopenia? |
Over production of Leukocytes and the other is abnormally low WBC count |
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What are platelets? |
Cytoplasmic fragments of really large cells called Megakaryocytes |
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What does the hormone Thrombopoietin do? |
Regulates the formation of platelets. |
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Describe Hemostasis |
1. Vascular spasm- Blood vessel constricts reducing blood loss
2. Platelet plug formation-platelets attach to collagen fibres. Platelets release chemicals that make nearby platelets sticky.
3. Coagulation- Fibrin forms a mesh which traps RBC and platelets forming a clot
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Describe pathway from prothrombin activator to Fibrin |
Promthrobin activator coverts plasma protein prothrombin to active enzyme thrombin. Thrombin cataylzes clotting factor fibrinogen into fibrin. |
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What is clot retraction? |
Platelets contract (actin and myosin like in muscles) squeezing serum out from the mass compacting clot and pulling ruptured edges of blood vessel together. Platelet derived growth factor is released stimulating muscle cells and fibroblasts to divide and rebuild wall. |
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What is fibrinolysis? |
The removal of unneeded clots that can take up to 2 days by fibrin digesting enzyme called plasmin |
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What is essential for production of haemoglobin? |
Iron, vitamin B12 and folic acid |
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What is main difference between Fibrinogen and Fibrin? |
Fibrinogen is water soluble, fibrin is not. Most actors are inactive in blood and become enzymes after being active. |
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What is Spectrin and what does it do? |
Is a network of proteins on RBC plasma membrane that maintains the biconcave shape of erythrocyte. Allows it to change shape e.g. going through smaller capillaries |
