Assertion: Solubilities of proteins is minimum at the isoelectronic point.
Reason: At isoelectronic point , protein molecules behaves as a zwitter ion.

Options

A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but reason is not the corret explanation of the assertion.
C. If assertion is true but reason is false.
D. If the assertion and the reason both are false.

Explanation

To analyze the given assertion and reason, we will break down the concepts involved step by step.

### Step 1: Understand the Assertion
The assertion states that "the solubility of proteins is minimum at the isoelectric point."

- **Isoelectric Point (pI)**: This is the pH at which a particular molecule or protein carries no net electrical charge. At this point, the positive and negative charges within the protein balance each other out.

### Step 2: Understand the Reason
The reason provided is that "at the isoelectric point, protein molecules behave as zwitter ions."

- **Zwitter Ion**: A zwitter ion is a molecule that has both positive and negative charges but is overall neutral. In the case of proteins, at the isoelectric point, the amino groups (NH3+) are positively charged, and the carboxyl groups (COO-) are negatively charged, resulting in a zwitter ion form.

### Step 3: Connect the Assertion and Reason
Now, we need to connect the assertion and the reason:

- At the isoelectric point, since proteins exist as zwitter ions, they do not interact well with water molecules. This is because the neutral charge reduces their solubility in an aqueous environment. Therefore, the assertion that the solubility of proteins is minimum at the isoelectric point is supported by the reason that at this point, proteins behave as zwitter ions.

### Conclusion
Both the assertion and the reason are correct, and the reason correctly explains why the assertion is true.

### Final Answer
- **Assertion**: True
- **Reason**: True
- **Conclusion**: Both the assertion and reason are correct, and the reason supports the assertion.

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