How much percentage of animals on this earth are regulations ?

Options

A. 0.02
B. 0.03
C. 0.04
D. 0.01

Answer

To determine the percentage of animals on Earth that are regulators, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definitions**:
- **Regulators**: These are organisms that maintain homeostasis, meaning they can keep a constant internal environment regardless of external conditions. Examples include mammals and birds.
- **Conformers**: These organisms do not maintain a constant internal environment; their internal conditions change with the external environment. Most animals and plants fall into this category.

2. **Identify the Proportion of Regulators**:
- According to the information provided, it is stated that 99% of animals and plants are conformers. This implies that only a small percentage of organisms are regulators.

3. **Calculate the Percentage of Regulators**:
- If 99% are conformers, then the remaining percentage that are regulators can be calculated as:
\[ 100\% - 99\% = 1\% \]
- This means that 1% of animals are regulators.

4. **Convert to Decimal Form**:
- To express this percentage in decimal form, we convert 1%:
\[ 1\% = \frac{1}{100} = 0.01 \]

5. **Select the Correct Option**:
- From the options provided (A: 0.02, B: 0.03, C: 0.04, D: 0.01), the correct answer is:
- **Option D: 0.01**.

### Final Answer:
The percentage of animals on Earth that are regulators is **0.01%**.

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