Question

For some proteins, small molecules are integral to their structure and function. Enzymes can synthesise some of these small molecules, whereas others, called vitamins, must be ingested in the food we eat.
Which of the following molecules is NOT classified as a vitamin but does require the ingestion of a vitamin for its production?
Answer

retinal

biotin

zinc

haeme

Answer 1

1:Haeme is a non-protein component of hemoglobin.

2: Zinc is an essential mineral that is naturally present in some foods.

3:Biotin: A colorless crystalline vitamin essential for the activity of many enzyme systems and found in large quantities in liver, egg yolk, milk, and yeast.

retinal: a yellowish to orange aldehyde derived from vitamin A that in combination with proteins forms the visual pigments of the retinal rods and cones.

Answer 2

Zinc is in vitamin D right?

Answer 3

Vitamin D is a group of fat-soluble secosteroids responsible for enhancing intestinal absorption of calcium and phosphate. In humans, the most important compounds in this group are vitamin D3 (also known as cholecalciferol) and vitamin D2 (ergocalciferol). Cholecalciferol and ergocalciferol can be ingested from the diet and from supplements. The body can also synthesize vitamin D (specifically cholecalciferol) in the skin, from cholesterol, when sun exposure is adequate (hence its nickname, the "sunshine vitamin").

Although vitamin D is commonly called a vitamin, it is not actually an essential dietary vitamin in the strict sense, as it can be synthesized in adequate amounts by most mammals exposed to sunlight. A substance is only classified as as an essential vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from its diet. In common with other compounds commonly called vitamins. (Copied from Wikipedia.)

Alright now...Zince is in Vitamin D..
Biotin Vitamin B.
Retinal: Vitamin A