Chapter 28, Problem 28.23AP

Interpretation Introduction

Interpretation:

Hormone and its functions have to be explained. It should be determined that how is the presence of a hormone detected by its target.

Concept Introduction:

Hormones are chemical substances synthesized in small amounts by endocrine tissues and carried by blood stream to another tissue, where it acts as a messenger to regulate the function of the target tissue or organ.

A given hormone usually affects only a limited number of cells, which are called target cells and it responds to a hormone because it bears receptors for the hormone.

There are three major classes of molecules which function as hormones in vertebrates and they are,

• Amino acid derivatives: It is a derivative of an amino acid formed by the reaction at the side chain functional group, carboxylic acid group, and amino group or by the replacement of a hydrogen atom by heteroatom.
• Polypeptides: Polypeptides are organic polymers having several amino acids attached to each other in a chain.
• Steroid: Steroids are a type of organic compound having a molecular structure with four rings connected to each other.