If the distance between two consecutive base pairs is 0.34 nm then the length of DNA for a human diploid cell is

Options

A. `6.6 xx 10^9 m`
B. `6.6 xx 10^9 bp x 0.34 m`
C. `2.2 metres`
D. `6.6 xx 10^-9 m`

Answer

To calculate the length of DNA in a human diploid cell, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of Human DNA**:
- A human diploid cell contains 46 chromosomes, which consist of approximately 6.4 billion base pairs.

2. **Identify the Distance Between Base Pairs**:
- The distance between two consecutive base pairs is given as 0.34 nanometers (nm).

3. **Calculate the Total Length of DNA**:
- To find the total length of DNA, we can use the formula:
\[ \text{Total Length} = \text{Number of Base Pairs} \times \text{Distance Between Base Pairs} \]
- Plugging in the values:
\[ \text{Total Length} = 6.4 \text{ billion base pairs} \times 0.34 \text{ nm} \]
- Convert 6.4 billion to a numerical value:
\[ 6.4 \text{ billion} = 6.4 \times 10^9 \]
- Now, substituting this into the equation:
\[ \text{Total Length} = 6.4 \times 10^9 \text{ base pairs} \times 0.34 \text{ nm} \]
- Calculate the total length in nanometers:
\[ \text{Total Length} = 2.176 \times 10^9 \text{ nm} \]

4. **Convert Nanometers to Meters**:
- Since 1 meter = \(10^9\) nanometers, we convert the total length from nanometers to meters:
\[ \text{Total Length in meters} = \frac{2.176 \times 10^9 \text{ nm}}{10^9} = 2.176 \text{ meters} \]

5. **Final Result**:
- The length of DNA for a human diploid cell is approximately 2.2 meters.