Which of the following is not an industrial or biological importance of osmosis ?

Options

A. Movement of water from soil into plant roots and upper portion of plant .
B. Salting of meat to prevent bacterial action
C. Reverse osmosis for desalination of sea water
D. Filling of ink in a fountain pen

Explanation

To determine which of the following options is not an industrial or biological importance of osmosis, we will analyze each option step by step.

### Step 1: Analyze Option A - Movement of water from soil into the plant roots
- **Explanation**: Osmosis is the movement of water from an area of higher concentration to an area of lower concentration through a semi-permeable membrane. In this case, water moves from the soil (where it is in higher concentration) into the roots of the plant (where it is in lower concentration). This is a fundamental biological process that allows plants to absorb water and nutrients.
- **Conclusion**: This is an application of osmosis.

### Step 2: Analyze Option B - Salting of meat to prevent bacterial action
- **Explanation**: When salt is applied to meat, it creates a hypertonic environment outside the bacterial cells. Water moves out of the bacterial cells (where there is a higher concentration of water) into the salt solution (where there is a lower concentration of water). This process causes the bacterial cells to shrink and ultimately die, thus preserving the meat.
- **Conclusion**: This is also an application of osmosis.

### Step 3: Analyze Option C - Reverse osmosis for desalination of seawater
- **Explanation**: Reverse osmosis is a process where pressure is applied to overcome osmotic pressure, allowing water to move from a concentrated saline solution to a less concentrated solution. This is widely used for desalination, making seawater drinkable by removing salt and impurities.
- **Conclusion**: This is a significant industrial application of osmosis.

### Step 4: Analyze Option D - Filling of ink in a fountain pen
- **Explanation**: The filling of ink in a fountain pen occurs due to capillary action, which is the ability of a liquid to flow in narrow spaces without the assistance of external forces. This is not related to osmosis, as it does not involve the movement of water across a semi-permeable membrane.
- **Conclusion**: This is not an application of osmosis.

### Final Answer
Based on the analysis, the option that is not an industrial or biological importance of osmosis is **D: Filling of ink in a fountain pen**.

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