What condition is characterized by a deficiency of red blood cells?

Anemia is indeed characterized by a deficiency of red blood cells, which are crucial for transporting oxygen throughout the body. This condition arises when there are insufficient healthy red blood cells to meet the body's needs, leading to symptoms such as fatigue, weakness, and paleness. The deficiency can result from various factors, including nutritional deficiencies (like iron, vitamin B12, or folate), bone marrow disorders, chronic diseases, or blood loss.

In contrast, leukemia is a cancer of the blood or bone marrow characterized by an overproduction of abnormal white blood cells. Thrombocytopenia refers to a low platelet count, which affects blood clotting, while polycythemia is the opposite condition, involving an overproduction of red blood cells. Each of these other conditions has distinct characteristics and implications for health, making anemia unique in its specific deficiency of red blood cells.