Which option best describes a function of the skeletal system?

• A. Provides storage of energy for muscles
• B. Provides support and protection for other tissues, stores calcium and other minerals, forms blood cells
• C. It creates immune cells to fight infection
• D. It controls hormone secretion

Answer: (B)

The skeletal system mainly provides support and protection for the body's soft tissues and organs, stores calcium and other minerals for use throughout the body, and houses the bone marrow where blood cells are formed. Bones give a framework that supports the body and shield delicate structures—think of the skull protecting the brain and the rib cage protecting the heart and lungs. They also serve as a mineral reservoir, releasing calcium and other minerals as needed to maintain balance in the body. Inside certain bones, red bone marrow carries out hematopoiesis, producing red blood cells, white blood cells, and platelets. This combination matches the description of a function that includes support, protection, mineral storage, and blood cell formation.

Energy storage for muscles isn’t a skeletal function, since energy reserves are stored mainly in adipose tissue and fat within yellow marrow rather than in bone. Hormone secretion and immune cell production are handled by other systems, with bone marrow contributing to blood cell formation (including some immune cells) but not describing the skeletal system alone.