On comparing the proportion of elements found in human tissue and Earth's crust, which one of the following is found to be negligible?

Options

A. Silicon
B. Calcium
C. Magnesium
D. Sulphur

Answer

To solve the question of which element is found to be negligible when comparing the proportions in human tissue and Earth's crust, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Elements**: The elements we need to compare are Silicon, Calcium, Magnesium, and Sulfur.

2. **Research the Proportions in Earth's Crust**:
- Silicon: Approximately 27.7%
- Calcium: Approximately 3.6%
- Magnesium: Approximately 2.1%
- Sulfur: Approximately 0.03%

3. **Research the Proportions in Human Tissue**:
- Calcium: Approximately 1.5%
- Magnesium: Approximately 0.1%
- Sulfur: Approximately 0.3%
- Silicon: Negligible (not significantly present)

4. **Compare the Proportions**:
- **Silicon**: Very high in Earth's crust (27.7%) but negligible in human tissue.
- **Calcium**: Present in both (3.6% in crust, 1.5% in human tissue).
- **Magnesium**: Present in both (2.1% in crust, 0.1% in human tissue).
- **Sulfur**: Present in both (0.03% in crust, 0.3% in human tissue).

5. **Conclusion**: From the comparison, it is clear that Silicon is the element that is found to be negligible in human tissue compared to its significant presence in the Earth's crust.

### Final Answer:
Silicon is found to be negligible in human tissue when compared to its abundance in the Earth's crust.

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