Calcium And Growrh

Question 1

Usually when does the brain stop growing?

Answer 1

Around 8-12 years old

Question 2

What hormones influence growth

Answer 2

Cortisol
Growth hormones
Sec hormones
Thyroid hormones
Insulin
Vit D
Parathyroid

Question 3

You see a lack of brain development, skull growth and delayed tooth eruption and enlarged tongue, what could be the cause

Answer 3

Hypothyroidism

Question 4

Sex hormone effects mediated by increased secretion of growth hormone and IGF-1

Answer 4

While both insulin and IGF-1 can promote the uptake and utilization of glucose by cells, they have different mechanisms of action and different target tissues. Insulin primarily acts on muscle and adipose tissue to promote glucose uptake, while IGF-1 primarily acts on bone and muscle tissue to promote growth and development.

Question 5

What is the significance of epiphyseak growth plates?

Answer 5

For epiphyseal growth plates, if they close because of like sex hormones, cannot elongate any more, only appositional growth

That’s why after puberty where there was a increase in sex hormone levels, the epiphyseal growth plate closure was accelerated.

Question 6

Does high levels of cortisol inhibit growth or promote growth

Answer 6

Inhibit, as well as promotes bone resorption (osteoporosis?) and protein catabolism

That is why children with high levels of stress have growth retarding effects

Question 7

Excess growth hormone in children causes what

Answer 7

Gigantism

Question 8

Excess growth hormone in adults cause what

Answer 8

Acromegaly - giant feet and hands due to appositional growth + big mandible

Question 9

How do you identify a tumour of the pituitary gland on an X-ray

Answer 9

Enlarged sella turcica

Question 10

What happens to our cells as we age

Answer 10

Decline in ability to divide and replace old cells

Errors in DNA as they divide, accumulation of dna damage , , abnormal proteins produced, damage to organelles

Question 11

3 important substances in calcium homeostasis

Answer 11

Calcitonin - c cells in thyroid
Parathyroid hormone - parathyroid
Vitamin D - skin

Question 12

Can vitamin K be made in the body?

Answer 12

Yes by the bacteria in your intestines

Question 13

Does insulin or cortisol increase bone mass;decrease bone resorption

Answer 13

Insulin

Question 14

What activates vitmain D (D3 to calcitriol)

Answer 14

Enzymes from the liver and kidneys , regulated by PTH

Question 15

Name of activated vitamin D

Answer 15

Calcitriol=
1,25 (OH)2 cholecalciferol

Question 16

Where is vitamin D converted to active form?

Answer 16

Kidneys

Question 17

Functions of vitamin D

Answer 17

Increase calcium absorption at intestine and kidney

Calcium release from bones

Question 18

Osteitis fibrosa cystica

Question 19

Normal calcium level in blood

Answer 19

2.6mmol/L