Question

rbc has no nucleus then why do we call them cell?

Answer 1

It would be unwise to say RBCs don't have nucleus.They do have nucleus.But in later stage the nucleus is being removed by the process called ENUCLEATION.They undergo this change so as to create more surface area to accomodate more amount of oxygenin the form of oxyhaemoglobin which is then carried to various parts of the body.  

Answer 2

Yes, of course, we can call them a cell.

When RBC is formed and gets matured in the Bone marrow matrix, it has a well-defined nucleus. And it is with the help of this nucleus they produce and concentrate the red pigment hemoglobin which is required for the transport of oxygen and the real purpose of them n the body.

With the DNA present in the cell, each RBC makes the proteins and even the antigens for blood group present in the surface.

After{ when they become a stage called reticulocyte⇒just 4 info} they lose their nucleus and starts to circulate in the blood.

The interesting thing is that they not only lack nucleus but lack almost all cell organelles even mitochondria.

Guessing how the hell they make energy?

They make from anaerobic respiration. The RBCs are well prepared before they enter the bloodstream and they know they will only live 120 days without a nucleus. this is only for transporting oxygen and carbon dioxide in our circulatory system. of course, they are a cell, they do all the functions and show metabolism by anaerobic respiration.


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I have answered all the details about RBCs. For more info or doubts you can ask me...