Under optimum condition Bacterial cells divide once in 20 minutes by binary fission. How many bacteria will be produced in 2 hours with same rate of division ?

Options

A. 8
B. 32
C. 128
D. 64

Explanation

To solve the problem of how many bacteria will be produced in 2 hours with a division rate of once every 20 minutes, we can follow these steps:

### Step 1: Convert the total time from hours to minutes
We know that 1 hour is equal to 60 minutes. Therefore, to convert 2 hours into minutes:
\[ 2 \text{ hours} = 2 \times 60 = 120 \text{ minutes} \]

### Step 2: Determine the number of divisions that occur in that time
Since the bacteria divide every 20 minutes, we need to find out how many 20-minute intervals fit into 120 minutes:
\[ \text{Number of divisions} (n) = \frac{\text{Total time}}{\text{Time per division}} = \frac{120 \text{ minutes}}{20 \text{ minutes}} = 6 \]

### Step 3: Use the formula for bacterial growth
The formula for the total number of bacteria after n divisions is given by:
\[ \text{Total number of bacteria} = 2^n \]
Where \( n \) is the number of divisions.

### Step 4: Calculate the total number of bacteria
Now that we have \( n = 6 \), we can calculate the total number of bacteria:
\[ \text{Total number of bacteria} = 2^6 = 64 \]

### Conclusion
Therefore, the total number of bacteria produced in 2 hours is **64**.

---