Question

Briefly write a short note on hormones

Answer 1

Hormones are chemical messengers produced by endocrine cells and glands (pituitary, thyroid, adrenals, pancreas, gonads, etc.) that travel in the blood or act locally to coordinate physiology and behavior. They regulate growth and development, metabolism, fluid and electrolyte balance, stress responses, and reproduction. Chemically, hormones are peptides/proteins (e.g., insulin, growth hormone), steroids (e.g., cortisol, estrogen, testosterone), or amines (e.g., adrenaline, thyroid hormones). Water-soluble hormones bind cell-surface receptors and usually use second-messenger systems; lipid-soluble hormones cross cell membranes and bind intracellular receptors to alter gene transcription. Hormone levels are tightly controlled by feedback loops (mostly negative feedback) and by neural inputs. Clinical imbalances—deficiency or excess—cause disorders such as diabetes, hypothyroidism/hyperthyroidism, Cushing’s or Addison’s disease, and reproductive dysfunctions.