Chapter 2 - Endocrine gland hormones

Question 1

What does the thyroid secrete, its target cells and effects

Answer 1

• Thyroxine (T4) and triiodothyronine (T3). Most body cells. Thyroxine is less active but lasts longer, 80-% Increases metabolic rate, O2 consumption, heat production
• Calcitonin. Bones, Kidney. Decreases calcium and phosphate levels in the blood by reducing breakdown of bone and reabsorption in kidneys

Question 2

What does the parathyroid secrete, its target cells and effects

Answer 2

• Parathormone. Bones and kidneys. Increases calcium levels in blood and phosphate excretion in urine
• in bones, increased calcium release into blood
• in Intestines, increased calcium absorbed from food
• In kidneys, increased calcium reabsorbed into blood

Question 3

What does the thymus secrete, its target cells and effects

Answer 3

• Thymosins. T-lymphocytes. Stimulates development and maturation of T-lymphocytes

Question 4

What does the adrenal cortex secrete, its target cells and effects

Answer 4

corticosteroids:

• Aldosterone. Kidneys. Increases reabsorption of sodium ions and excretion of potassium ions through sodium potassium pumps
• Cortisol. Most body cells. promotes normal metabolism and promotes repair of damaged tissues

Question 5

What does the adrenal medulla secrete, its target cells and effects

Answer 5

• Adrenaline. Most body tissues. Helps to prepare the body for a reaction to a threatening situation
• Noradrenaline. most body tissues. Similar to adrenaline, in particular increases the rate and force of heart beat

Question 6

What does the pancreas secrete, its target cells and effects

Answer 6

• Insulin. Most body cells. Secreted by the beta cells of the islets of langerhans, decreases blood glucose level
• Glucagon. Liver and fat storage tissues. Secreted by the alpha cells of the islets of langerhans, Increases blood glucose level

Question 7

What does the testes secrete, its target cells and effects

Answer 7

• Androgens (testosterone). many tissues. development of male sex characteristics

Question 8

What does the Ovaries secrete, its target cells and effects

Answer 8

• Oestrogen. Many tissues. development of female sex characteristics, regulates menstrual cycle
• Progesterone. Uterus and mammary glands. Regulates menstrual cycle and pregnancy, mammary glands for milk

Question 9

How does insulin decrease blood glucose levels

Answer 9

Promotes the uptake of glucose from the blood by cells of the body.

• In the liver, causes the conversion of glucose to glycogen and fat.
• in skeletal muscles, causes the formation of glycogen from glucose.
• In fat storage tissue, causes glucose to be converted into fat

Question 10

Cause of other tissues that’s secrete hormones

Answer 10

• Stomach and small intestine secrete hormones that coordinate the exocrine glands of the digestive system
• Kidneys secrete the hormone erythropoietin stimulate production of red blood cells by the bone marrow
• Heart secretes a hormone that helps reduce blood pressure
• The placenta secretes hormones during pregnancy that help maintain the pregnancy