Study the statements and choose the correct answer
Statement a. Amino acids are amphoteric.
Statement b. All amino acids are necessary for our body.

Options

A. a and b are correct
B. a and b are wrong
C. a is correct, b is wrong
D. a is wrong, b is correct

Answer

To analyze the statements provided in the question, we will evaluate each statement one by one.

### Step 1: Evaluate Statement A
**Statement A:** Amino acids are amphoteric.

- **Explanation:** Amino acids contain both a carboxylic acid group (-COOH) and an amine group (-NH2). The carboxylic acid group can donate a proton (H+) and become negatively charged (-COO^-), while the amine group can accept a proton and become positively charged (-NH3^+). This dual ability to act as both an acid and a base is what makes amino acids amphoteric. At a specific pH known as the isoelectric point, amino acids exist in a zwitterionic form, where they have both a positive and a negative charge but are overall neutral.

### Step 2: Evaluate Statement B
**Statement B:** All amino acids are necessary for our body.

- **Explanation:** There are 20 standard amino acids, and they can be categorized into essential and non-essential amino acids. Essential amino acids cannot be synthesized by the body and must be obtained through diet, while non-essential amino acids can be synthesized by the body. However, both types are necessary for various physiological functions, including protein synthesis, enzyme function, and metabolic processes. Therefore, while not all amino acids are essential in the sense that they must come from the diet, all amino acids play important roles in the body.

### Conclusion
Both statements are true:
- Statement A is true because amino acids are indeed amphoteric.
- Statement B is also true because all amino acids, whether essential or non-essential, are necessary for the body.

### Final Answer
The correct answer is that both statements are true.

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