Choose 3 body systems, and explain how they interact with one another.

Digestive system, skeletal system and cardiovascular system
The digestive and cardiovascular systems are held up and protected by the skeletal system
The cardiovascular system receives blood from the bone marrow in the skeletal system and delivers oxygenated blood to the digestive system to allow the muscles there to work
The digestive system provides a means to use calcium for bone production and repair in the skeletal system and gives nutrients to be transported round the body to the cardiovascular system

Your nervous system is involved with the excretory systems,and is controlled by the autonomic nervous system. The autonomic nervous function is controlled by your body with out conscious thought, the brain and spinal cord work together to carry out these tasks.

The structures in the kidney that filter the blood are called "nephron filters", so the answer is C. Nephrons. This filtering is performed primarily through tiny capillaries in the structure