erythrocytes and platelets

Question 1

describe the shape of erythrocytes(RBCs)

Answer 1

biconcave discs ~7micrometres in diameter

Question 2

what are erythrocytes made up of(roughly)

Answer 2

no nucleus or organelles, 1/3 is haemoglobin and they have a flexible cytoskeleton to allow deformation to move through spaces smaller than themselves

Question 3

how long do erythrocytes normally stay in circulation and how are they removed after this

Answer 3

approximately 4 months, removed mainly by spleen and liver

Question 4

what are platelets

Answer 4

small cell fragments, about 2micrometers diameter, found in large numbers in blood

Question 5

describe the structure of a platelet

Answer 5

they play a key role in hemostasis(prevention of blood loss), also involved in extrusion of granules and in clot retraction

Question 6

describe the structure of platelets

Answer 6

have a well developed cytoskeleton, some organelles, no nucleus and contain some granules