As human red blood cells mature, they lose their nuclei. As a result of this loss, which process would be impossible for mature red blood cells to carry out?

The correct answer is cell division.

In the process of cell division parent cell divides into two or more daughter cells. Before every cell division DNA replicates and there are two copies of DNA molecules. After the division every daughter cell gets a one copy of DNA molecule, and they are genetically identical.

Cell nucleus contains DNA which is needed for cell division. As human red blood cells lose their nucleus during maturation they also lose DNA and they are not able to carry out cell division.

As the human red blood cells, they lose their nuclei, as a consequence, they would lose the tendency to replicate themselves. The nucleus comprises the DNA, which constitutes the blueprint or the instructions for development, growth, reproduction, and function. If there would be no nucleus, there will be no DNA. Therefore, in the absence of DNA, the cell cannot go through the process of replication, as they lack instructions to do so.

However, this offers many benefits for the cell, that is, it offers more space for hemoglobin that leads to more transportation of oxygen, and this leads to the bi-concave shape of the cell that seems to assist in the process of diffusion.