Vitamin-Bl is named so because
**Core Concept**
Vitamin B12, also known as Cobalamin, is a crucial water-soluble vitamin that plays a vital role in the synthesis of DNA, fatty acid, and amino acid metabolism. It is essential for the maintenance of the nervous system and the formation of red blood cells.
**Why the Correct Answer is Right**
Vitamin B12 is named so because it contains a cobalt ion at its core, which is derived from the Latin word "cobaltum". This cobalt ion is essential for the vitamin's biological activity, particularly in the synthesis of methionine from homocysteine and the metabolism of fatty acids and amino acids. The cobalt ion is also responsible for the vitamin's role in maintaining the health of the nervous system.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not relate to the etymology of Vitamin B12. The name "Vitamin B12" is derived from the vitamin's position in the B-complex group of vitamins, not from a specific chemical characteristic.
**Option B:** This option is incorrect because it is a characteristic of Vitamin B6, not Vitamin B12. Vitamin B6, also known as Pyridoxine, contains a pyridine ring in its structure.
**Option C:** This option is incorrect because it is a characteristic of Folic Acid, not Vitamin B12. Folic Acid is a synthetic form of Vitamin B9, which contains a pterin ring in its structure.
**Clinical Pearl / High-Yield Fact**
It is essential to note that Vitamin B12 deficiency can lead to neurological symptoms such as numbness, weakness, and cognitive impairment. Additionally, a deficiency in Vitamin B12 can cause megaloblastic anemia, characterized by the production of large, immature red blood cells.
**Correct Answer: C. This option is incorrect because it is a characteristic of Folic Acid, not Vitamin B12.**