vitamin a2
Học thuậtThân thiện
Definition
Noun: A viscous alcohol that is less active in mammals than vitamin A1. It is a specific form of vitamin A, also known as dehydroretinol, found in some freshwater fish and other animal tissues.
Usage
This is a scientific and biochemical term. It is used to specify a particular chemical form of vitamin A, distinguishing it from the more common and active form, vitamin A1 (retinol).
Examples
- Noun:
- The liver of this freshwater fish is a rich source of vitamin A2.
- In their study, the researchers compared the biological activity of vitamin A2 to that of retinol.
- The chemical structure of vitamin A2 differs from vitamin A1 by one double bond.
Advanced Usage
- Biochemical Context: The term is primarily used in nutritional science, biochemistry, and comparative physiology to discuss the presence and function of different vitamin A forms in various species.
- The visual pigments in some amphibians are based on vitamin A2 rather than A1.
Variants and Related Words
- Dehydroretinol: The systematic chemical name for vitamin A2.
- Vitamin A1 (Retinol): The more common and active form of vitamin A in mammals, often contrasted with vitamin A2.
- Retinoid: The broader class of chemical compounds related to or derived from vitamin A, which includes both A1 and A2 forms.
Synonyms
- Dehydroretinol (This is the direct chemical synonym).
Notes
- This is a highly specialized term. In general health, nutrition, and everyday contexts, the simple term "vitamin A" almost always refers to vitamin A1 (retinol) and its precursors (like beta-carotene). The distinction between A1 and A2 is relevant mainly in specific scientific discussions.
Noun
- a viscous alcohol that is less active in mammals than is vitamin A1