Vitamin C

Question 1

What are the characteristics of Water Soluble Vitamins?

Answer 1

1. Soluble in water
2. Simple diffusion (large amount)
3. Through a carrier-mediated process (smaller amounts)
4. Distributed in aqueous phases of the cell

Question 2

Ascorbic Acid

Answer 2

VITAMIN C

Question 3

Vitamin C Nomenclature:

Answer 3

◦Antiascorbutic vitamin

◦“fresh food” vitamin

Question 4

Biologically active forms of vitamin C

Answer 4

◦L-ascorbic acid

◦L-dehydroascorbic acid

Question 5

Vitamin C is Most easily destroyed by:

Answer 5

heat, alkali, light, oxygen; Fe & Cu)

Question 6

Cannot be synthesized by human

Answer 6

gulonolactone oxidase

Question 7

Vitamin C is absorbed in the ______

Answer 7

Absorbed in GI

Question 8

Vitamin C is not stored in the _____

Answer 8

Tissues

Question 9

Highest amount of Vitamin C is found in the ____

Answer 9

liver, adrenal glands, and glandular organs

Question 10

what is the vitamin C that transport and store in the plasma?

Answer 10

ascorbic acid in free form

Question 11

what is the vitamin C that transport and store in the cell?

Answer 11

glucose transporter & active transport system and moves it into to the cell as dehydroascorbic acid where it is readily reduced as ascorbic acid

Question 12

Vitamin C when excreted in the urine

Answer 12

dehydroascorbate,
ketogulonate,
ascorbate-2-sulfate
oxalic acid

Question 13

how many g/day is excreted as ascorbic acid

Answer 13

2 g/day

Question 14

FUNCTIONS OF VITAMIN C

Answer 14

1. Antioxidant properties
2. Formation & maintenance of intercellular cementing substances
3. Wound healing & fracture healing
4. Collagen Synthesis
5. Promotes resistance to infection

Question 15

translocates fatty acid from the cytosol to the mitochondria needed for fatty acid oxidation
Vit C needed to convert carnitine from trimethyllysine

Answer 15

Carnitine

Question 16

A Peptide which act as hormones and hormone-releasing factors: oxytocin, cholecystokinin, gastrin

Answer 16

Amidated hormones

Question 17

Food Sources

Answer 17

◦Plant: Fresh fruits (anonas, bayabas, datiles,cashew, strawberry, melon, papaya, camichile, citrus fruits, mangoes), broccoli, red bell pepper, tomatoes and GLV
◦Animal: kidney and heart

Question 18

Catecholamine Hormones

Answer 18

epinephrine and norephinephrine

Question 19

DEFICIENCY OF VITAMIN C

Answer 19

Scurvy

Question 20

◦Legs in “frog’s position”

◦Flexing as a response to tender, painful, and swollen thighs, delayed dentition, and skeletal growth

Answer 20

Infantile scurvy

Question 21

Effects of Excessive Intakes

Answer 21

• Gastrointestinal disturbances and diarrhea
• Increased possibility of forming renal oxalate and uric stones
• Can give a false positive urinary glucose test (Db test)

Question 22

Vitamin C promotes this mineral absorption

Answer 22

Fe

Question 23

Fe inhibits this mineral’s abbsorption

Answer 23

Cu

Question 24

Vitamin C Prevents binding of ___ to ____ in intestinal cells

Answer 24

Cu

metallothione

Question 25

Vitamin C Prevents oxidation of _____, _____, _____

Answer 25

tetrahydrofolate,

Vit. A and PUFAs

Question 26

High Vit.C destroys what vitamin?

Answer 26

B12

Question 27

Vit C’s destruction is hastened by the presence of what minerals?

Answer 27

Fe & Cu

Question 28

lack of ___ prevents absorption of Vit C.

Answer 28

HCL

Question 29

any excess over ___ mgs Vit C is excreted.

Answer 29

1.2mgs

Question 30

Richest source of vit C

Answer 30

Puerto Rico Cherry, acerola

Question 31

Vitamin C is the most unstable of all vitamins.

true or false

Answer 31

true