When a cell is placed in 0.25 M concentrated suger solution, theere is no change in it. So the external solutionis called

Options

A. Hypertonic
B. Isotonic
C. Hypotonic
D. None of the above

Answer

To solve the question, we need to understand the behavior of cells when placed in different types of solutions based on solute concentration. Here's a step-by-step breakdown of the solution:

### Step 1: Understand the Types of Solutions
There are three main types of solutions based on solute concentration:
- **Hypertonic Solution**: The concentration of solute is greater outside the cell than inside. This causes water to move out of the cell, leading to cell shrinkage.
- **Isotonic Solution**: The concentration of solute is equal inside and outside the cell. There is no net movement of water, so the cell remains unchanged.
- **Hypotonic Solution**: The concentration of solute is lower outside the cell than inside. Water moves into the cell, which can cause the cell to swell or even burst.

### Step 2: Analyze the Given Situation
The question states that when a cell is placed in a 0.25 M concentrated sugar solution, there is no change in the cell. This indicates that the concentration of solute inside the cell is equal to the concentration of solute in the external solution.

### Step 3: Identify the Type of Solution
Since there is no change in the cell, it implies that the external solution has the same solute concentration as the internal environment of the cell. Therefore, the external solution must be **isotonic**.

### Step 4: Choose the Correct Option
From the options provided:
- A: Hypertonic
- B: Isotonic
- C: Hypotonic
- D: None of the above

Since we have determined that the external solution is isotonic, the correct answer is **Option B: Isotonic**.

### Final Answer
The external solution is called **isotonic**.

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