Daily dose of folic acid for women of child bearing age is?
**Core Concept**
Folic acid supplementation is essential for women of childbearing age to prevent neural tube defects in the developing fetus. The recommended daily dose of folic acid is based on the prevention of these birth defects.
**Why the Correct Answer is Right**
The correct answer is **400 micrograms**. This dose is crucial for the prevention of neural tube defects, such as spina bifida and anencephaly. Folic acid works by promoting DNA synthesis and repair, which are essential for the rapid cell division and growth that occur during embryonic development. The enzyme dihydrofolate reductase (DHFR) is involved in the conversion of folic acid to its active form, tetrahydrofolate (THF), which is then used in various biochemical reactions, including nucleic acid synthesis.
**Why Each Wrong Option is Incorrect**
**Option A:** 100 micrograms is too low to be effective in preventing neural tube defects.
**Option B:** 2 milligrams is excessive and may cause adverse effects, such as gastrointestinal symptoms.
**Option C:** 0 micrograms implies no supplementation, which is not recommended for women of childbearing age.
**Clinical Pearl / High-Yield Fact**
A common mnemonic to remember the daily dose of folic acid is "400 for all": 400 micrograms for all women of childbearing age to prevent neural tube defects.
**Correct Answer:** C. 400 micrograms.