Adenine of DNA is equimolar with

Options

A. Uridine
B. Thymine
C. Guanine
D. Cytosine.

Answer

To solve the question "Adenine of DNA is equimolar with," we need to understand the pairing of nitrogenous bases in DNA. Here’s a step-by-step solution:

### Step 1: Understand the Structure of DNA
DNA is composed of nucleotides, which include a sugar, a phosphate group, and a nitrogenous base. The nitrogenous bases are classified into two categories: purines and pyrimidines.

**Hint:** Recall that purines have a double-ring structure, while pyrimidines have a single-ring structure.

### Step 2: Identify the Nitrogenous Bases
The nitrogenous bases in DNA are:
- **Purines:** Adenine (A) and Guanine (G)
- **Pyrimidines:** Thymine (T) and Cytosine (C)

**Hint:** Remember that adenine and guanine are the purines, while thymine and cytosine are the pyrimidines.

### Step 3: Understand Base Pairing
In DNA, adenine pairs with thymine, and guanine pairs with cytosine. The pairing occurs through hydrogen bonds:
- Adenine (A) pairs with Thymine (T) using **2 hydrogen bonds**.
- Guanine (G) pairs with Cytosine (C) using **3 hydrogen bonds**.

**Hint:** Think about how the base pairing rules dictate the relationships between the bases.

### Step 4: Determine Equimolar Relationships
Since adenine pairs with thymine, the amount of adenine present in a DNA molecule is equal to the amount of thymine. This means that adenine and thymine are present in a 1:1 ratio.

**Hint:** Consider the definition of "equimolar" and how it applies to the base pairing in DNA.

### Step 5: Conclusion
Therefore, adenine of DNA is equimolar with thymine. The correct answer is **thymine (T)**.

**Final Answer:** Adenine of DNA is equimolar with **Thymine** (Option B).