This image shows the RBCs of a person with sickle cell anemia, an inherited condition. What effects could the shape of these cells have on the efficiency of the circulatory system?

The shape of the abnormal red blood cells in sickle cell anemia can affect the efficiency of the circulatory system by obstructing the flow of blood through the arteries.

Explanation:

Red blood cells are the cells responsible for transporting oxygen and carbon dioxide throughout the body, and their spherical shape allows them to pass through blood vessels of any calibre.

A red blood cell in sickle cell disease loses its spherical shape, acquiring a half-moon shape, which can lead to its accumulation inside the arteries and produce a blockage, decreasing the efficiency of the circulatory system.  

The arterial obstruction may lead to a decrease in oxygenation in the sites that are irrigated by that artery.

Learn more:

Sickle cell anemia link