Vitamin B12 Cobalamin

Question 1

what is the other name of vitamin b12

Answer 1

cobalamin

Question 2

what is the cofactor of vitamin b12

Answer 2

cobalamin

Question 3

what are the dietary sources of vitamin b12

Answer 3

1 meat
2 fish
3 intestinal bacteria
4 eggs
5 diary products
6 yeast

Question 4

what is the defeciency of vitamin b12

Answer 4

there is a decrease in the secretion of intrinsic factor (IF) and or Hcl
long term vegetarian diet and malabsorption
prencious anemia and megaloblastic anemia

Question 5

how is cobalamin separated from digested foods?

Answer 5

by pepsin
hcl
haptocorrin (attached salivary protein)

Question 6

the vitamin is released by

Answer 6

pancreatic enzymes

Question 7

IF which is a glycoprotein is secreted by

Answer 7

partial cells of gastric mucoasa

Question 8

where does IF binds to B12

Answer 8

in the ileum

Question 9

IF-B12 complex is taken to the ileum epithileal cells via

Answer 9

cubilin receptors

Question 10

when IF-b12 complex dissociates what happens?

Answer 10

transcobalamin II (TcII) binds to b12 forming holotranscobalamin

Question 11

Holotranscobalamin is released to plasma.
This complex is taken into the cells (liver
and other tissues) via ____________
Vitamin is released from TcII and found in
cytosol as _____________ in
mitochondria as _____________________________