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State biological importance of hormones. |
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Answer» Solution :(i) Peptide hormones : The role of insulin maintains the blood sugar level within the narrow limit. Insulin is RELEASED in response to rapid rise in glucose level in glucose. On the other hand, hormone glucagon tends to increase the glucose level in the blood. These two hormones together regulate the glucose level in the blood. (ii) Amine hormones : Norepinephrine mediate responses to external stimuli. Thyroxine hormone produced by the thyroid gland is an iodinated derivative of amino acid tyrosine. Abnormally low level of thyroxine leads to hypothyroidism which is characterised by lethargyness and obesity. Increased level of thyroxine causes hyperthyroidism. Low level of iodine in the diet may lead to hypothyroidism and enlargement of the thyroid gland. This condition is largely being controlled by the Epinephrine and addition of sodium iodide to the commercial table salt (Iodised salt). (iii) Steroid hormones : Steroid hormones are produced by adrenal CORTEX and gonads (i.e., testes in males and ovaries in females). Hormones produced by the adrenal cortex plays very important role in the functions of the body. For example, glucocorticoids control the carbohydrate metabolism, modulate inflammatory reactions, and are involved in reactions to stress. The mineralocorticoids control the level of excretion of water or salt by the kidney. If adrenal cortex does not function properly then of the RESULTS may be Addison.s disease characterised by hypoglycaemia, weakness and increased susceptibility to stress. The disease is fatal unless treated by glucocorticoids and mineralocorticoids. Hormones released by gonads are responsible for development of secondary sex characters. Testosterone is a major sex hormone produced in males. It is responsible for development of secondary male characteristics such as deep voice, facial hair and general physical CONSTITUTION. Estradiol is the main female sex hormone which is responsible for the development of female characteristics and PARTICIPATES in control of menstrual cycle. Progesterone is responsible for preparing the uterus for implantation of fertilised egg. |
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