All are true about Vitamin B|2, except –
**Vitamin B12 Core Concept**
Vitamin B12 is a crucial water-soluble vitamin that plays a significant role in the synthesis of DNA, fatty acid, and amino acid metabolism, as well as the maintenance of the nervous system. It is the largest and most complex vitamin, requiring a specific transport mechanism to be absorbed in the small intestine.
**Why the Correct Answer is Right**
Vitamin B12 is essential for the synthesis of methionine from homocysteine, which involves the enzyme methionine synthase. This enzyme requires vitamin B12 as a cofactor to catalyze the reaction. Additionally, vitamin B12 is necessary for the maintenance of the nervous system, and deficiency can lead to neurological disorders such as subacute combined degeneration.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not provided.
* **Option B:** This option is not provided.
* **Option C:** This option is not provided.
* **Option D:** This option is not provided.
**Clinical Pearl / High-Yield Fact**
Vitamin B12 deficiency can lead to a megaloblastic anemia, which is characterized by the production of abnormally large red blood cells that are unable to function properly. This type of anemia is often associated with neurological symptoms, such as weakness, fatigue, and numbness in the extremities.
**Correct Answer:** Not provided