Growth Hormone

Question 1

3 factors affecting growth besides GH

Answer 1

1) Diet
2) Stress levels
3) Levels of growth-influencing hormones (IGF-1, IGF-2)

Question 2

Metabolic effects of GH

Answer 2

1) Increase in fat breakdown
2) Increase in fatty acids in blood
3) Increase in blood glucose level
4) Ensures fat rathe than glucose is metabolized during fasting

Question 3

Main function of IGF-1

Answer 3

Mediates growth effects postnatally

Question 4

Main function of IGF-2

Answer 4

Stimulates prenatal growth, is not regulated by GH

Question 5

Steps in elongation of bones

Answer 5

1) Chondrocytes undergo cell division
2) Older chondrocytes enlarge
3) Calcification of extracellular matrix
4) Dead chondrocytes cleared away by osteoclasts
5) Osteoblasts deposit bone over remnants of disintegrating cartilage

Question 6

How is GH regulated

Answer 6

Negative feedback loops
Ex. IGF-1 inhibits production of GHRH and GH

Question 7

Conditions associated with lack of GH

Answer 7

Growth hormone deficiency

Question 8

Conditions associated with excess GH

Answer 8

Acromegaly

Question 9

Test to diagnose GH disorders and example

Answer 9

GH stimulation tests
Ex. administer arginine to raise GH levels, measure the ability of pituitary to secrete GH