Number of H bonds present between adenine and thymine in formation of Nucleic acid

Explanation

To determine the number of hydrogen bonds present between adenine and thymine in the formation of nucleic acids, we can follow these steps:

### Step 1: Identify the Structure of Adenine and Thymine
- Adenine is a purine nitrogenous base, while thymine is a pyrimidine nitrogenous base.
- Draw the structures of both adenine and thymine to visualize how they interact.

### Step 2: Analyze the Hydrogen Bonding
- In the DNA double helix, adenine pairs with thymine through hydrogen bonds.
- Look at the specific atoms involved in hydrogen bonding. Adenine has an amine group (-NH2) and thymine has a carbonyl group (C=O) and a nitrogen atom (N).

### Step 3: Count the Hydrogen Bonds
- From the structures, you can see that adenine forms two hydrogen bonds with thymine:
1. One hydrogen bond occurs between the nitrogen atom of adenine and the carbonyl oxygen of thymine.
2. The second hydrogen bond occurs between the nitrogen atom of thymine and the hydrogen atom of adenine.

### Conclusion
- Therefore, the number of hydrogen bonds present between adenine and thymine in the formation of nucleic acid is **2**.

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