How many of the following statements are correct
(I) polysaccharides are present in an acid insoluble pool.
(II) protein is a homopolymer.
(III) In a Polynucleotide chain, the last amino acid called the N-terminal amino acid.
(IV) The tertiary structure is absolutely necessary for the many biological activities of Proteins.

Options

A. 4
B. 3
C. 2
D. 1

Answer

To determine how many of the given statements are correct, let's analyze each statement one by one:

### Step 1: Analyze Statement I
**Statement I:** Polysaccharides are present in an acid insoluble pool.
- **Explanation:** This statement is correct. Polysaccharides, such as starch and cellulose, are not soluble in acids and therefore can be found in an acid-insoluble pool.

### Step 2: Analyze Statement II
**Statement II:** Protein is a homopolymer.
- **Explanation:** This statement is also correct. Proteins are made up of amino acids, which are the same type of building blocks, making them homopolymers.

### Step 3: Analyze Statement III
**Statement III:** In a polynucleotide chain, the last amino acid is called the N-terminal amino acid.
- **Explanation:** This statement is incorrect. In a polynucleotide chain (which refers to nucleic acids like DNA and RNA), the last nucleotide is referred to as the C-terminal nucleotide, not the N-terminal. The N-terminal refers to the start of a protein or polypeptide chain.

### Step 4: Analyze Statement IV
**Statement IV:** The tertiary structure is absolutely necessary for the many biological activities of proteins.
- **Explanation:** This statement is correct. The tertiary structure of proteins is crucial for their functionality, as it determines the protein's shape and, consequently, its activity.

### Conclusion
Now, let's summarize the correctness of each statement:
- Statement I: Correct
- Statement II: Correct
- Statement III: Incorrect
- Statement IV: Correct

Thus, **three out of the four statements are correct**.

### Final Answer
The number of correct statements is **3**.

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