Which type of cell does not contain a nucleus enabling it to carry more hemoglobin? leucocyte white blood cell nerve cell erythrocyte

Erythrocytes also called as red blood cells. These are the cells which does not possess nucleus. They exhibit a pigment named as hemoglobin, the heme  component of the hemoglobin has affinity for oxygen. It carries oxygen to all the parts of the body.

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.