+Glands and the hormones that secrete (Ch2)

Question 1

Pineal gland

Answer 1

decreases in size after puberty. role is not entirely known but it secretes melatonin, involved in regulation of sleep patterns.

production of melatonin is stimulated by darkness and inhibited by light.

Question 2

Thyroid gland

Answer 2

Secretes:
Thyroxine + Triiodothyronine: (most body cells) increases metabolic rate and therefore oxygen consumption and heat production.
(Thyroxine [T4] is less active but lasts longer)

Calcitonin: (kidneys, bones) decreases calcium and phosphate levels in the blood.

Question 3

Parathyroid gland

Answer 3

Secretes:
Parathyroid hormone: (bones + kidneys) increases calcium levels in the blood and phosphate secretion in the urine.

Question 4

Thymus

Answer 4

Secretions:
Thymosins: (T-lymphocytes) stimulate the development and maturation of disease fighting cells T-lymphocytes.

Question 5

Adrenal cortex

Answer 5

Secretions:
(Corticosteroids)
Aldosterone: (kidneys) decreases amount of sodium in urine (reabsorption) and increases potassium in urine (excretion).

Cortisol: (most body cells) promotes normal metabolism; helps the body deal with stress; promotes repair of damaged tissues.

Question 6

Adrenal medulla

Answer 6

Secretions:
Adrenaline (epinephrine): (most body tissues) it helps to prepare the body for reaction to a threatening situation - concerned with fight or flight responses.

Noradrenaline: (most body tissues) it increases the rate and force of the heartbeat.

Question 7

Pancreas

Answer 7

Secretions:
Insulin: (most body cells) stimulates uptake of glucose; lowers blood glucose level.

Glucagon: (liver and fat storage tissues) stimulates the breakdown of glycogen and fat; increases blood glucose level

Question 8

Testes

Answer 8

Secretions:
(Androgens) Testosterone: (many tissues) stimulate sperm production, growth of skeleton and muscles, and development of male characteristics.

Question 9

Ovaries

Answer 9

Secretions:
Oestrogen: (many tissues) stimulate the development of female sexual characteristics; regulate the menstrual cycle.

Progesterone: (uterus and mammary glands) regulates menstrual cycle and pregnancy; prepares mammary glands for milk secretion.