Vitamin D Metabolism Disoders

Question 1

2 key functions of vitamin D:

Answer 1

Facilitate intestinal absorption of calcium

Inhibit PTH synthesis and secretion

Question 2

Calcitriol = _________________ = active form of vitamin D

Answer 2

1,25-dihydroxycholecalciferol

Question 3

Vitamin D deficiency is due to 2 key reasons:

Answer 3

1. Diet with low vitamin D and low phosphorus
2. Reduced UV light exposure

Question 4

Rickets is vitamin D deficiency in:

Answer 4

Young, growing animals with open growth plates

Question 5

Osteomalacia is vitamin D deficiency in

Answer 5

Adult animals With closed growth plates

Question 6

Osteomalacia literally means

Answer 6

Bone softening

Question 7

Low vitamin D can cause

Answer 7

Defective mineralization of bones; soft, weak bones

Question 8

Ricketts is defective mineralization and ________ _______

Answer 8

Endochondral ossification

Question 9

Animals with ricketts are more prone to pathological fractures because:

Answer 9

Retained cartilage is not as strong as bone

Question 10

The key area of bone that is affected with ricketts is:

Answer 10

The physes (growth plates)