Osmosis is observed during

Options

A. Absorption of water by seed coat
B. Ascent of sap in xylem
C. Apoplastic lateral conduction of water
D. Movement of water from xylem into sieve tubes during loading of food

Answer

To answer the question "Osmosis is observed during," we need to analyze the options provided and determine which one involves the process of osmosis.

### Step-by-Step Solution:

1. **Understanding Osmosis**:
- Osmosis is the movement of water molecules through a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration. It is a passive process and is crucial for maintaining cell turgor and overall plant health.

2. **Evaluating the Options**:
- **Option A: Absorption of water by seed coat**: This process is primarily known as imbibition, where seeds absorb water to swell and begin germination. It does not involve osmosis in the traditional sense, as it is more about the physical absorption of water.
- **Option B: Ascent of sap in xylem**: This refers to the upward movement of water and minerals from the roots through the xylem to the rest of the plant. This process involves osmosis as water moves from areas of higher concentration in the soil to lower concentration in the roots and subsequently through the xylem.
- **Option C: Apoplastic lateral conduction of water**: This process involves the movement of water through the cell walls and intercellular spaces, bypassing the cell membranes. It does not primarily involve osmosis.
- **Option D: Movement of water from xylem into sieve tubes during loading of food**: This process involves the movement of water due to hydrostatic pressure and is not a direct example of osmosis.

3. **Conclusion**:
- Based on the analysis, the correct answer is **Option B: Ascent of sap in xylem**, as this process involves osmosis.

### Final Answer:
Osmosis is observed during the ascent of sap in xylem.

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