Question

Which are hormones ? Give an example for each of the following ?
(a) Steroid hormones
(b) Polypeptide hormones
(c) Amino acid derivatives

Answer 1

Hint: Endocrine system achieves coordination and integration by the release of some substances which are physiologically active and are directly released into the bloodstream.

Complete answer:
Hormones are chemical messengers that are secreted directly into the blood, which carries them to organs and tissues of the body to exert their functions. There are many types of hormones that act on different aspects of bodily functions and process like –
- Development and growth.
- Metabolism of food items.
- Sexual function and reproductive growth and health.
- Cognitive function and mood.
- Maintenance of body temperature and thirst.
(a) Steroid Hormones – A steroid hormone is a steroid that acts as hormone. Steroid hormones can be grouped into two classes ; Cortico steroids (Typically made in the Adrenal cortex, hence cortico) and Sex steroids (typically made in the gonads or placenta). They help in controlling the metabolism, immunity functions, inflammation and development of various sexual characteristics.
Example – Estrogens, progesterone and Androgens.
(b) Polypeptide Hormones – A polypeptide is a chain of amino acids. Amino acids bond together with peptide bonds in order to form a polypeptide. They function to regulate a wide range of physiological functions which includes growth, energy and appetite metabolism, and reproductive physiology.
Example – Insulin.
(C) Amino acid derivatives – Derivatives of amino acid resulting from reaction at an amino group, carboxyl group, side chain functional group, or from the replacement of any hydrogen by hetero atom. They help in regulating sleep cycle by secreting melatonin.
Example – Adrenaline and Noradrenaline.

Note: Some of the major endocrine glands in the body include –
Pituitary gland, Pineal gland, Thymus, Thyroid, Adrenal glands, Pancreas, Testes, Ovaries
These organs secrete hormones in microscopic amounts and it takes only very small amounts to bring about major changes in the body; even a very slight excess of hormone secretion can lead to disease states, as can the slightest deficiency in hormones.