Points to Remember

Plant and Animal Hormones (Science)

Points to Remember

·                 Auxins are produced at the tip of stems and roots from where they migrate to the zone of elongation.

·                 Cytokinins are the plant hormones that promote cell division or cytokinesis in plant cells.

·                 Gibberellins induce the formation of seedless fruit and parthenocarpic fruits.

·                 Abscisic acid is a growth inhibitor which regulates abscission and dormancy. It increases tolerance of plants to various kinds of stress.

·                 Ethylene is a gaseous plant hormone mainly concerned with maturation and ripening of fruits.

·                 The pituitary gland regulates and controls other endocrine glands and so is called as the “Master gland”.

·                 The hormones secreted by the thyroid gland are triiodothyronine (T3), and tetraiodothyronine or thyroxine (T4)

·                 The parathormone act on bone, kidney and intestine to maintain blood calcium levels.

·                 Pancreas secretes insulin and glucagon.

·                 They maintain blood glucose level.

·                 Adrenal cortex secrete coritsol and aldosterone and adrenal medulla secretes epinephrine and norepinephrine.

·                 The sex glands are of two types the testes and the ovaries which secrete testosterone and estrogens respectively.