Rate of heartbeat is maximum in

Options

A. man
B. whale
C. elephant
D. mouse

Answer

To determine which organism has the maximum heart rate among man, whale, elephant, and mouse, we can follow these steps:

### Step 1: Understand Heart Rate
Heart rate refers to how many times the heart contracts and relaxes in a minute. It is measured in beats per minute (bpm).

### Step 2: Normal Heart Rate for Humans
The normal heart rate for a healthy human is approximately 72 beats per minute.

### Step 3: Principle of Heart Rate
The heart rate is inversely proportional to the size of the organism. This means that larger organisms tend to have a lower heart rate, while smaller organisms tend to have a higher heart rate.

### Step 4: Compare the Organisms
- **Man**: 72 bpm
- **Whale**: Generally has a much lower heart rate due to its large size.
- **Elephant**: Also has a low heart rate, similar to that of the whale.
- **Mouse**: Being significantly smaller than the other organisms, it is expected to have a higher heart rate.

### Step 5: Conclusion
Given the principle that smaller organisms have higher heart rates, and knowing that the mouse is the smallest among the options provided, we can conclude that the mouse has the maximum heart rate.

### Final Answer
The rate of heartbeat is maximum in the mouse.

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