Name the factor essential for absorption of vitamin B12

Answer

**Step-by-Step Solution:**

1. **Identify the Vitamin**: The question asks about the absorption of vitamin B12. It's important to know that vitamin B12 is crucial for various bodily functions, including red blood cell formation and neurological function.

2. **Understand the Absorption Process**: Vitamin B12 absorption occurs primarily in the small intestine, specifically in the ileum. However, for vitamin B12 to be effectively absorbed, certain factors must be present.

3. **Recognize the Key Factor**: The essential factor for the absorption of vitamin B12 is known as the **intrinsic factor**.

4. **Define Intrinsic Factor**: Intrinsic factor is a glycoprotein that is secreted by the parietal cells located in the stomach lining.

5. **Explain Its Role**: The intrinsic factor binds to vitamin B12 in the stomach, which is necessary for the vitamin to be absorbed in the ileum of the small intestine. Without intrinsic factor, vitamin B12 cannot be effectively absorbed, leading to deficiencies.

6. **Conclusion**: Thus, the factor essential for the absorption of vitamin B12 is the **intrinsic factor**.

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