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(a) Describe the condition known as varicose veins.
(b) What is the role of blood platelets in the clotting process?

Answer Text:
a)- Weakened or defective valve in veins; causing blood/body fluid/tissue fluid to accumulate; leading to swelling or flabby veins.
b)- When exposed to air, they rupture/burst, releasing thromboplastin/ thrombokinase enzyme that initiate clotting
process by neutralizing heparin, which is anticlotting factor in the blood.