What are hormones? Give examples. State their functions.

Explanation

The secretions of endocrine glands (ductless glands) are called hormones. Hormones are derived from amino acid derivatives or peptides and proteins or steroids. They are easily diffusible. They have low molecular weight and affect biological processes. They are produced in very small amounts and regulate vital b ody functions.
Examples:
(1) Adrenaline and non-adrenaline hormones are derived from amino acids. These two hormones enhance the functions of the sympathetic nervous system like increasing glucose level in blood and lactic acíd in muscles.
(2) The hormone thyroxine is secreted by thyroid glands in the neck and it increases the rate of energy exchange and consumption of oxygen.
(3) Insulin is secreted in pancreas and it is a peptide hormone. Insulin controls the metabolism of carbohydrate by increasing
glycogens in muscles and oxidation of glucose in tissue and also lowers blood pressue.
(4) Sex hormones are produced by ovaries in females (esterogens d progesterone) and testes in males (androgens). It is a steroid rmone and helps in reproduction development and also are sponsible to develop secondary sexual characteristics in males and females.