AT/GC ratio in human being is

Options

A. `0.93 :1`
B. `1:0.93`
C. `1.52:1`
D. `0.93:1`

Answer

To find the AT/GC ratio in human beings, we follow these steps:

### Step 1: Understand the Components
The AT/GC ratio is calculated using the amounts of the nitrogenous bases in DNA:
- A = Adenine
- T = Thymine
- G = Guanine
- C = Cytosine

### Step 2: Define the Ratio
The ratio is defined as:
\[ \text{AT/GC} = \frac{A + T}{G + C} \]
This means we will sum the quantities of Adenine and Thymine and divide that by the sum of Guanine and Cytosine.

### Step 3: Calculate the Ratio for Humans
In humans, the AT/GC ratio has been determined to be approximately:
\[ \text{AT/GC} = 1.5 \]
This indicates that the combined amount of Adenine and Thymine is 1.5 times greater than the combined amount of Guanine and Cytosine.

### Step 4: Compare with Given Options
The options provided are:
1. 0.93 : 1
2. 1 : 0.93
3. 1.5 : 1
4. 0.93 : 1

From our calculation, the correct ratio is:
\[ 1.5 : 1 \]
Thus, the correct answer is option 3.

### Conclusion
The AT/GC ratio in human beings is 1.5 : 1.

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