Homeostasis

Homeostasis maintains optimal conditions for enzyme action throughout the body, as well as all cell functions.

In the human body, these include the control of:

• blood glucose concentration
• body temperature
• water levels

These automatic control systems may involve nervous responses (nervous system) or chemical responses (endocrine system ).

Nervous system

The human nervous system consists of:

• the central nervous system (CNS) – the brain and spinal cord
• the peripheral nervous system – nerve cells that carry information to or from the CNS

A diagram showing the central and peripheral nervous system