About 90% of the cytoplasm is occupied by __________.

Explanation

**Step-by-Step Solution:**

1. **Understanding Cytoplasm Composition**: The cytoplasm is a gel-like substance found within the cell membrane, and it contains various components, including the cytosol and cytoplasmic inclusions.

2. **Identifying Major Component**: Among the various constituents of the cytoplasm, the primary component is water.

3. **Percentage of Water in Cytoplasm**: It is known that approximately 90% of the cytoplasm is made up of water, which contributes to its colorless appearance.

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