Question

Question: Vitamins A, D, E, and K are fat‑soluble vitamins. Classify the following phrases as describing vitamin A, vitamin D, vitamin E, or vitamin K. :

Options:

(1) hormone precursor and visual pigment

(2) production takes place in skin

(3) deficiency can cause dry skin

(4) regulates gene expression in epithelial tissue

(5) hormone precursor derived from a steroid

(6) regulates calcium uptake by intestine

(7) prevents oxidative damage to membrane lipids

(8) antioxidant

(9) cofactor

(10) functions in fibrin formation

Answer 1

Fat soluble vitamins are those which soluble in fat which more likely oils and they donot dissolve in water. They are much abundant in fat foods and are much absorbed into bloodstream when we eat with fat.

Fat soluble vitamins- vitamin A, vitamin D, vitamin E and vitamin K are classified on the basis of given phrases as-

Vitamin A

* Hormone precursor and visual pigment.- Vitamin A(retinal) plays an important role in vision of the eye.

* Antioxidant. - Vitamin A is antioxidant which protect cell from free radicals.

* Deficiency causes dry skin. Deficiency of Vitamin A cause eczema which is dry skin.

* Cofactor - vitamin A is a cofactor.

Vitamin D

* Hormone precursor derived from a steroid. - Vitamin D is a steroid hormone they are relatef to estrogen, testosterone etc.

* Regulates calcium uptake by intestine. - they regulates active calcium in the proximal duodenum and jejunum and oppose to ileum.

* production takes place in skin. - skin is responsible for the formation of vitamin D when exposure to sunlight (ultraviolet rays cause vitamin D formation).

* Antioxidant.

Vitamin E

* Antioxidants. - Vitamin E is also a antioxidant which protect cells from free radicals from damaging.

* Prevent oxidative damage to membrane lipids. - They prevent by scavenging free radicals.

Vitamin K

* Function in fibrin formation. - They have a direct role in fibrin formation.

* Cofactor -  Vitamin K serve as a cofactor for carboxylase that catalyses carboxylisation of glutamic acid.

*  Antioxidant - Vitamin K also has this property.