Out of the total energy received by herbivorous from producers, how much is passed to carnivorous?

Options

A. 0.05
B. 0.1
C. 0.25
D. 0.5

Answer

To solve the question regarding the energy transfer from producers to herbivores and then to carnivores, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Trophic Levels**:
- Producers (like plants) are at the first trophic level.
- Herbivores, which consume producers, are at the second trophic level (primary consumers).
- Carnivores, which consume herbivores, are at the third trophic level (secondary consumers).

2. **Energy Transfer Concept**:
- According to the 10% rule in ecology, only about 10% of the energy from one trophic level is transferred to the next level. The remaining 90% of energy is lost due to metabolic processes, heat, and other factors.

3. **Calculate Energy Received by Herbivores**:
- If we assume that producers provide a certain amount of energy (let's say 1000 kcal), herbivores will receive 10% of that energy.
- Energy received by herbivores = 10% of 1000 kcal = 100 kcal.

4. **Calculate Energy Passed to Carnivores**:
- When carnivores eat herbivores, they again receive only 10% of the energy that the herbivores have.
- Energy received by carnivores = 10% of 100 kcal = 10 kcal.

5. **Expressing the Energy Transfer as a Fraction**:
- The question asks how much energy from the total energy received by herbivores is passed to carnivores.
- The fraction of energy passed from herbivores to carnivores is 10 kcal (energy received by carnivores) out of 100 kcal (energy received by herbivores).
- This can be expressed as:
\[ \frac{10 \text{ kcal}}{100 \text{ kcal}} = 0.1 \]

6. **Conclusion**:
- Therefore, the answer to the question is **0.1** (which corresponds to option B).