Question

The swelling in feet and ankles of an aged person due to sitting continuously for long hours during travel, is reduced by soaking the feet in warm salt water. This is because of:

• A. Reverse Osmosis
• B. Osmosis
• C. Edema
• D. Diffusion

Answer 1

The Correct Option is B

Oedema, or swelling, occurs when fluid accumulates in the body's tissues. This can happen due to various reasons, including prolonged sitting, which can reduce blood and lymph flow, leading to fluid buildup.

Soaking the feet in warm salt water can help reduce this swelling. The warmth of the water increases blood flow, while the salt (sodium chloride) in the water helps draw fluid out of the tissues.

Analyzing the Options

1. (A) Reverse Osmosis
   Reverse osmosis is a process where water is forced through a semipermeable membrane to remove contaminants. This is not the mechanism by which salt water reduces swelling.
2. (B) Osmosis
   Osmosis is the movement of water across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration. The salt in the water increases the solute concentration outside the cells, drawing water out of the cells and reducing swelling.
3. (C) Edema
   Edema is the condition of swelling, not the process by which it is reduced.
4. (D) Diffusion
   Diffusion is the movement of particles from an area of higher concentration to an area of lower concentration. While diffusion plays a role in many biological processes, it is not the primary mechanism by which soaking in salt water reduces swelling.

Conclusion

The correct answer is (B) Osmosis. Soaking the feet in warm salt water reduces swelling by increasing the solute concentration outside the cells, which draws water out of the cells through osmosis.

Answer 2

Osmosis is the process by which solvent molecules move from a region of lower solute concentration to a region of higher solute concentration through a semi-permeable membrane. In this case, the swollen feet have a higher concentration of fluid inside the cells (due to fluid accumulation) compared to the surrounding environment (warm salt water). Soaking the feet in warm salt water helps the fluid move out of the cells (osmosis), thereby reducing the swelling.

Other options:

(A) Reverse osmosis is a process where solvent moves from a higher concentration to a lower concentration, typically used in water purification. It is not related to this case.

(C) Edema refers to the condition of fluid retention and swelling, but it does not explain the mechanism behind the reduction of swelling.

(D) Diffusion is the movement of molecules from a region of higher concentration to a region of lower concentration, but it does not involve a semi-permeable membrane as in osmosis.