Which of the following describes sickle cell anemia?

Sickle cell anemia is a genetic blood disorder characterized by the production of abnormal hemoglobin, which leads to the distortion of red blood cells into a sickle or crescent shape. This altered shape affects the cells' flexibility and their ability to navigate through the bloodstream, particularly in small blood vessels. As a result, blood flow is impaired, leading to various complications such as pain crises, increased risk of infection, and organ damage due to reduced oxygen delivery.

The other options do not accurately describe sickle cell anemia. For instance, labeling it primarily as a respiratory condition misrepresents the fundamental nature of the disease, which is centered around blood and hemoglobin rather than respiratory function. Additionally, stating that sickle cell disease does not affect blood flow contradicts the central mechanism of the disorder, as the sickled cells can obstruct blood vessels. Finally, attributing the disease to a deficiency of iron in the blood is incorrect; sickle cell anemia is not caused by nutritional deficiencies but by a hereditary genetic mutation in the hemoglobin beta gene. Therefore, the accurate description focuses on the shape change in blood cells and its consequences on circulation and overall health.