Question

explain the role of the vitamin A and iron in our body list few food sources in 250 words​

Answer 1

Explanation:

Vitamin A is a group of unsaturated nutritional organic compounds that includes retinol, retinal, and several provitamin A carotenoids (most notably beta-carotene).[1][2] Vitamin A has multiple functions: it is important for growth and development, for the maintenance of the immune system, and for good vision.[3][4] Vitamin A is needed by the retina of the eye in the form of retinal, which combines with protein opsin to form rhodopsin, the light-absorbing molecule[5] necessary for both low-light (scotopic vision) and color vision.[6] Vitamin A also functions in a very different role as retinoic acid (an irreversibly oxidized form of retinol), which is an important hormone-like growth factor for epithelial and other cells.[4][7]

Answer 2

Vitamin A is a group of unsaturated nutritional organic compounds that includes retinol, retinal, and several provitamin A carotenoids (most notably beta-carotene). Vitamin A has multiple functions: it is important for growth and development, for the maintenance of the immune system, and for good vision.Vitamin A is needed by the retina of the eye in the form of retinal, which combines with protein opsin to form rhodopsin, the light-absorbing molecule necessary for both low-light (scotopic vision) and color vision. Vitamin A also functions in a very different role as retinoic acid (an irreversibly oxidized form of retinol), which is an important hormone-like growth factor for epithelial and other cells.

Chemical structure of retinol, one of the major forms of vitamin A

In foods of animal origin, the major form of vitamin A is an ester, primarily retinyl palmitate, which is converted to retinol (chemically an alcohol) in the small intestine. The retinol form functions as a storage form of the vitamin, and can be converted to and from its visually active aldehyde form, retinal.

All forms of vitamin A have a beta-ionone ring to which an isoprenoid chain is attached, called a retinyl group. Both structural features are essential for vitamin activity. The orange pigment of carrots (beta-carotene) can be represented as two connected retinyl groups, which are used in the body to contribute to vitamin A levels. Alpha-carotene and gamma-carotene also have a single retinyl group, which give them some vitamin activity. None of the other carotenes have vitamin activity. The carotenoid beta-cryptoxanthin possesses an ionone group and has vitamin activity in humans.

Vitamin A can be found in two principal forms in foods: