Biology XI: 22 Chem Cord & Integr(3 Human Endocrine System n Adrena

Human Endocrine System n Adrenal, Pancreas and Gonads Adrenal Gland Location: 1 pair − 1 gland at the anterior part of each kidney Catecholamine: Emergency hormones or hormones of fight or flight Increases alertness, pupilary dilation, piloerection (raising of hair) Increases heart beat, respiration rate Stimulates the breakdown of glucose, lipids and proteins Glucocorticoid: Stimulates gluconeogenesis, lipolysis and proteolysis Inhibits uptake and utilisation of amino acids Suppresses immune response by producing anti-inflammatory reaction (Example − Cortisol) Stimulates RBC production (Example − Cortisol) Mineralocorticoid: Example − Aldosterone Acts on renal tubule and stimulates re-absorption of Na+ and water Stimulates excretion of K+ Maintains electrolysis, osmotic pressure and blood pressure Androgenic steroids plays a role in the growth of axial, facial and pubic hair during puberty Pancreas Glucagon: Hyperglycemic hormone A peptide hormone Maintains the normal blood glucose level Acts on liver cells and stimulates glycogenolysis, resulting in hyperglycemia Stimulates gluconeogenesis (synthesis of glucose from sources like fats) Insulin: Hypoglycemic hormone A peptide hormone Stimulates liver cells to enhance the cellular glucose uptake and utilisation Moves the glucose from the blood to hepatocytes and adipocytes Converts glucose into glycogen Glucagon + Insulin = Maintain glucose homeostasis Prolonged hyperglycemia leads to diabetes mellitus (presence of glucose in urine); Treatment: Insulin therapy Testis Location: scrotal sac, in males Testis is composed of seminiferous tubules, and stromal or interstitial tissues. In the intertubular spaces, Leydig cells (interstitial cells) are present that secrete androgens, mainly testosterone. Functions of androgens: Development, maturation and functioning of the male accessory sex organs like vas deferens and seminal vesicles Stimulate muscular growth, growth of facial hair, low pitch voice, etc. Stimulatory role in spermatogenesis Act on the CNS and influence male sexual behaviour (libido) Anabolism of proteins and carbohydrates Ovary Location: inside abdomen, in females Hormones produced: Oestrogen and progesterone Ovary is composed of ovarian follicles and stromal tissues Ovarian follicles: Secrete oestrogen Functions of oestrogen: Growth and functioning of the female secondary sex organs Development of growing follicles and mammary glands Regulates female secondary sex characters (Examples − high pitch voice) Functions of progesterone: Acts on mammary glands and stimulates formation of alveoli-like structures storing milk Milk secretion