The Blood & Blood Vessels Flashcards

All 6 cards in this deck

How is a red blood cell (erythrocyte) adapted to transport oxygen?

Biconcave shape gives a large surface area for absorbing oxygen; no nucleus leaves more room for haemoglobin, which binds oxygen.

What are the roles of phagocytes and lymphocytes?

Phagocytes engulf and digest pathogens (flexible cytoplasm and a lobed nucleus let them change shape); lymphocytes produce antibodies.

What does blood plasma transport?

Blood cells and platelets, carbon dioxide, digested food (e.g. glucose, amino acids), urea, hormones and heat.

True or false? White blood cells start the clotting process when the skin is cut.

False. Platelets start the clotting process, forming a clot that seals the wound and keeps pathogens out.

How do the wall, lumen and valves of an artery, a vein and a capillary compare?

Artery: thick muscular and elastic wall, narrow lumen, no valves. Vein: thin wall, wide lumen, valves to stop backflow. Capillary: wall one cell thick, very narrow lumen, no valves.

Which property of an artery is being tested when a ring of artery tissue is stretched with masses and then allowed to return to its original length?

Its elasticity — elastic fibres in the thick wall let the artery stretch and recoil as blood surges through at high pressure.