hormones

Asked by palaksophia | 12th Jun, 2009, 09:53: PM

Expert Answer:

The various endocrine glands and their hormones are:

1) Pituitary Gland

i) Growth hormone (GH) - Stimulates growth of all body tissues but especially skeletal muscle and bone.

ii) Thyroid-stimulating hormone (TSH) promotes normal development and activity of the thyroid gland.

iii) Adrenocorticotropic hormone (ACTH) stimulates the adrenal cortex to release corticosteroids.

iv)  Gonadotropins—follicle-stimulating hormone (FSH) and luteinizing hormone (LH) regulate the functions of the gonads in both sexes. FSH stimulates sex cell production; LH stimulates gonadal hormone production.

v) Prolactin (PRL) promotes milk production in humans.

vi) The neurohypophysis stores and releases two hypothalamic hormones:

  • Oxytocin stimulates powerful uterine contractions, which trigger labor and delivery of an infant, and milk ejection in nursing women. 
  • Antidiuretic hormone (ADH) stimulates the kidney tubules to reabsorb and conserve water, resulting in small volumes of highly concentrated urine and decreased plasma osmolality.

 

2) Thyroid gland

Thyroxine (T4) and triiodothyronine (T3), which increase the rate of cellular metabolism.

 

3)  Parathyroid gland -

Parathyroid hormone (PTH), which causes an increase in blood calcium levels by targeting bone, the intestine, and the kidneys.

 

4) Adrenal Glands -

Hormones of adrenal cortex -

 

  • Mineralocorticoids (primarily aldosterone) regulate sodium ion reabsorption and potassium ion excretion by the kidneys. Sodium ion reabsorption leads to water reabsorption, and increases in blood volume and blood pressure. 
  • Glucocorticoids (primarily cortisol) are important metabolic hormones that help the body resist stress by increasing blood glucose, fatty acid and amino acid levels, and blood pressure.
  • Gonadocorticoids (mainly androgens) are produced in small amounts throughout life.

The adrenal medulla produces catecholamines (epinephrine and norepinephrine). The catecholamines enhance and prolong the fight-or-flight response to short-term stressors.

 

5) Pancreas

The endocrine portion (pancreatic islets) of pancreas releases insulin, glucagon, somatostatin and pancreatic polypeptide.

Glucagon - when blood levels of glucose are low, it stimulates the liver to release glucose to the blood.

Insulin -  is released when blood levels of glucose rise. It increases the rate of glucose uptake and metabolism by most body cells.

 

6) Ovaries

Estrogens -  Stimulate maturation of the female reproductive system and development of the secondary sex characteristics.

Progesterone - It works with estrogens in establishing the menstrual cycle.

 

7) Testes -

Testosterone - It promotes maturation of the male reproductive organs, development of secondary sex characteristics, and production of sperm by the testes.

 

8) Pineal gland -

Melatonin - It which influences daily rhythms and may have an antigonadotropic effect in humans.

 

9) Thymus gland -

thymosin and thymopoietins are important to the normal development of the immune response.

Answered by  | 13th Jun, 2009, 07:40: AM

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