The integumentary system is the physical system that forms the barrier between the external environment and the internal systems of the body. In humans, this system consists of skin, hair, nails, and ...

What Is the Endocrine System? The endocrine system is a network of glands in your body that make the hormones that help cells talk to each other. They’re responsible for almost every cell, organ, and ...

The endocrine system is the collection of glands that produce hormones, which are specialized proteins that regulate bodily functions. The endocrine system serves as the body's internal chemical ...

The autonomic nervous system is a complex network of cells that controls the body’s internal state. It regulates and supports many different processes, often outside of a person’s conscious awareness.