why are hormones needed
 

A hormone is a chemical messenger that regulates physiological processes in living organisms. It is secreted by a gland.

The regulation of the physiological processes, control, and coordination by hormones is governed by the endocrine system.

Hormones are needed because of the following reasons:

• Hormones act as chemical messengers.

• They act upon specific cells, tissues, or organs called the target sites.

• They are generally slow in action, but have long lasting effects.

• They either accelerate or inhibit a biochemical reaction. In this way, they regulate the vital reactions going on in our body.