red blood cells don't have DNA?

Question

huh? how does the cell live without DNA? i don't get it

i've heard it has DNA at the beginning of its life, where does it go?

and if you could process blood so that it contained only red blood cells, you wouldn't be able to figure out whose blood it was, right?

Answer 1

The evolution of the mammalian red blood cell has made it more efficient by making its dna obsolete. red blood cells are produce in bone marrow by other cells, so they never need to perform many cell functions other than flowing around through veins and arteries carrying oxygen and other nutrients. blood "type" refers to receptors on the outside of the blood cell, so that the immune system can correctly identify them as nonforeign bodies.

Answer 2

The red blood cells get rid of their nucleus (containing its DNA) early in their life. The reason they do that is because the nucleus is a bulky object, and retaining the nucleus will make it harder for RBCs to squeeze through tiny capillaries. It also allows the RBCs to assume a biconclave (sp?) shape, which increases its surface area for oxygen exchange.

Some animals, such as birds, have nucleated RBCs, and they survive just fine, so whether having a nucleus or not doesn't seem to matter that much.

Anyways, the RBCs can't live forever without DNA, so their lifespan is only about three months. Then they swell up and die, and are removed by macrophages in the spleen.

Answer 3

Mammalian red blood cells do not have the nucleus, and so they do not have DNA. They are a special type of cells for carrying oxygen. They have a short life (3 months), and new cells are made from bone marrow all the time.

You are right that you cannot do genotyping on red blood cells, but surface antigens are still there.

The red blood cells of birds have nucleus!

Answer 4

when red blood cells are newly produced, they have a nucleus which carries the dna. as they grow older the nucleus starts to disappear to make more room for oxygen.