Abstract

Steroids display varied biological functions and play a crucial role in the fascinating fields of biology, chemistry, and medicine.Steroids encompass wideranging natural products which are abundantly encountered in eukaryotic organisms. These exhibit a pivotal role in regulating the cellular functions of animals, plants, and fungi. Furthermore, they act as chemical messengers in the human body and get secreted in the systemic circulation and extracellular fluids, where they regulate metabolic, immune, and reproductive functions. Steroids are the fundamental components of cell membranes and serve primarily as signalling molecules. This chapter gives a comprehensive overview of physiologically active steroids in various organisms.The biological activities of various steroid classes have been discussed in detail. Glucocorticoids are a class of steroid hormones that regulate the metabolic processes involving the formation of glucose from amino acids and fatty acid deposition of glycogen in the liver. Another important group of hormones, called mineralocorticoids, helps in balancing water and electrolyte content in the body and primarily affects the kidney. The principal class of steroids viz. the sex hormones are essentially crucial for the development and maintenance of reproductive function and cause stimulation of secondary sexual characteristics in humans. To summarize, steroids stabilize and regulate the structure and functions of cellular membranes and play a crucial role in regulating growth and development.