Question

Why Rbc & Wbc, have a short life span?

Answer 1

RBC's lack nuclei and because of this their ability to self repair is limited. They have to physically deform constantly as they pass through capillary beds and this constant stress wears down their structural integrity over time.Red blood cells are the means of delivering oxygen to the body tissues - via blood flow through the circulatory system. They lack cell nucleus and most organelles so that they can accomodate maximum space for haemoglobin. Erythropoiesis is the process by which new red blood cells are produced and they have a functional lifetime of about 100-120 days.

Life span of WBC is 13-20 days after which they are destroyed in the lymphatic system. The function of WBC is to defend the body from infectious agents. most of the action of WBC is by the process of phagocytosis in which they also die. Examples of such WBC's are neutrophils and eosinophils.