nucleus i think
Nucleus
There are, in fact, several Organelles that are missing from a red blood cell (Erythrocyte), but the most significant one is the nucleus.
DNA
A red blood cell. Scientific name, Erythrocyte
It is biconcave in shape , mature red blood cell do not have nucleus,
A mature red blood cell does not have a nucleus or DNA.
a mature red blood cell
erythrocytes
An erythrocyte is a mature red blood cell.
No, it cannot divide since mature red blood cells have no nucleus. there are no chromosomes to replicate.
Then the mature red blood cell becomes a useless cell without any knowledge on how to do its job. It will then float through your blood stream until it is absorbed.
a mature red blood cell doesn't have a nucleus while an immature one does.
No Amoeba is not prokaryotic , it is Protist .
Till the pre-erythrocyte stage you have the nucleus in red blood cells. It is shed to get the mature red blood cell.
A reticulate red blood cell, or reticulocyte, is an immature red blood cell. In mammals, reticulocytes do not have a nucleus. They are slightly larger and appear more blue in colour (with standard stain) than mature red blood cells. A nucleated red blood cell is one which contains a nucleus. Mature mammalian red blood cells do not have a nucleus. In mammals, nucleated red blood cells are more immature than reticulocytes - and are not normally seen in peripheral circulation. They can be a sign of anaemia if seen on a blood smear. Birds and reptiles have nucleated mature red blood cells.