what is the role of platelets & why are sickle cells important?

Answer 1

Platelets help in blood clotting.
Sickle cells are RBCs that have a deformed shaped. They are sickled and don't hold on to oxygen well. They aren't important because they don't help the body in any way. They have no purpose.
But they are a key factor in Sickle Cell Disease which affects people with sickled cells. They usually have issues with ischemia, pain, and fatigue due to lack of O2.

Answer 2

Actually, people who are heterozygous for sickle cell, a condition called sickle cell trait, have some protection against malaria.

The alleles for sickle cell-type hemoglobin and normal hemoglobin are codominant. The cells will sickle when they are in oxygen deprivation. When the malarial parasite invades these cells, the parasite uses up the oxygen and makes the infected cells sickle and die. Meanwhile, the uninfected cells are fine.

Answer 3

Platelets are to coagulate blood, sickle cells aren't important it is a genetic disorder of the red blood cells