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Flashcards in Vitamin K Deck (21)
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1

what are the 4 different types of vitamin K

1. phylloquinone K1
2. menaquinone K2
3. menaquinones MK-4 to MK-6
4. menadione K3

2

bacteria in the colon produce

menaquinones (little absorbed)

3

the amounts of menaquinones produced in colon are not sufficient for body needs

T

4

what foods provide the most phylloquinones

broccoli, kale, swiss chard, turnip, watercress, collard greens, spinach, salad greens

5

how are menaquinones synthesized in the colon

absorbed via passive diffusion (not well due to lack of bile salt emulsification)

6

what delivers vitamin K to the liver

chylomicron

7

______ take up phylloquinone and synthesize menaquinone (MK-4)

extrahepatic tissues

8

principal vitamer in tissues other than the liver

menaquinone -4

9

are vitamin K levels high or low in the liver

low (less than B12)

10

what is the vitamin k dependent enzyme responsible for carboxylation

gamma-glutamyl carboxylase

11

vitamin ___ has the most potent gamma-carboxylation activity (MK-4)

K2

12

what is required for the protein to become functional and enable it to chelate calcium and interact with other compounds

post-translational carboxylation

13

found primarily in the liver associated with the RER

gamma-glutamyl carboxylase

14

4 of 13 blood coagulation proteins require

post translational carboxylation (II (prothrombin),VII, IX, and X)

15

anticoagulation factors ___, ____, and ___ require post translational carboxylation

C, S, and Z

16

what are the 4 vitamin K dependent proteins

1. osteocalcin (osteoblast)
2. matrix Gla protein (mobilization of bone Ca)
3. kidney Gla protein (renal reabsorption of Ca)
4. growth arrest - specific protein (Gas6)

17

low intake of vitamin K is associated with

low bone mineral density

18

women treated with anticoagulants during pregnancy leading to bone abnormalities and impaired neurological development

fetal warfarin syndrome

19

doses greater than ___ of vitamin e interfere with vitamin k

800IU

20

deficiency of vitamin k causes

hemorrhagic disorders due to under-carboxylated blood clotting factors inability to bind calcium for thrombin generation

21

no tolerable upper limit except for

menadione: cause hemolytic anemia and liver damage