Organism level systems

The nervous system allows us to react to our surroundings very quickly and to coordinate our behavior. It comprises millions of neurones and electrical impulses pass along them very quickly.

The endocrine system secretes hormones into the bloodstream from glands throughout the body. Hormones produce an effect on specific target organs in the body.

Homeostasis is the regulation of conditions in the body. Diabetes is a condition where the body cannot regulate its blood glucose levels.