Define haemostasis, describe the briefly about the mechanisms of clotting.
Spontaneous arrest or prevention of bleeding by physiological processes is called haemostasis.
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Describe the various stages involved in platelet plug formation
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What is the role of calcium in blood clotting process
Calcium act as a catalyst in many stages of cascade reaction. However, Calcium deficiency do not produce coagulation disorder’s because –
- Only traces of Ca are required for coagulation and the calcium ion very rarely falls to such low levels.
- Even, if may very severe Calcium deficiency occurs,it produce other symptoms like tetany before coagulation disorder’s develop.
Differentiate Adult hemoglobin and Fetal hemoglobin ?
Adult hemoglobin
- two alpha chains and two beta chains.
- lower affinity for oxygen than Fetal Hemoglobin.
- present in adults
- binds to 2,3-diphosphoglycerate (2,3-DPG) to release oxygen
- delivers oxygen to tissues and removes carbon dioxide
Fetal hemoglobin
- two alpha chains and two gamma chains.
- higher affinity for oxygen than Adult Hemoglobin
- present during fetal development and decreases after birth
- does not bind to 2,3-DPG, which allows it to bind to oxygen more effectively.
- delivers oxygen from mother’s blood to fetal tissues