Select the wrong statement wrt the biomolecules

Options

A. Majority of enzymes contain a nonprotein part called prosthetic group
B. Thylakoids are arranged one above the other like stack of coins forming a granum
C. Building blocks of lipid are amino acids
D. Cross-over occurs at pachytene stage of meiosis I.

Answer

To solve the question regarding the wrong statement with respect to biomolecules, we will analyze each of the provided statements one by one.

### Step 1: Analyze the first statement
**Statement:** Majority of the enzymes contain a non-protein part which is called as a prosthetic group.

**Analysis:** This statement is correct. Many enzymes are proteins that may have non-protein components known as prosthetic groups. These groups are essential for the enzyme's activity. For example, in enzymes like peroxidase or catalase, the heme group acts as a prosthetic group.

**Conclusion:** This statement is true.

### Step 2: Analyze the second statement
**Statement:** Thylakoids are the structural and functional units of the chloroplast, stacked to form the grana.

**Analysis:** This statement is also correct. Thylakoids are indeed the membrane-bound structures within chloroplasts that are involved in the light-dependent reactions of photosynthesis. They are organized in stacks known as grana.

**Conclusion:** This statement is true.

### Step 3: Analyze the third statement
**Statement:** The building block of lipids are amino acids.

**Analysis:** This statement is incorrect. Lipids are primarily composed of fatty acids and glycerol, not amino acids. Amino acids are the building blocks of proteins, not lipids.

**Conclusion:** This statement is false.

### Step 4: Analyze the fourth statement
**Statement:** The crossover occurs at the pachytene stage of meiosis I.

**Analysis:** This statement is correct. The pachytene stage of prophase I in meiosis is where crossing over occurs, allowing for genetic recombination.

**Conclusion:** This statement is true.

### Final Answer
Based on the analysis, the wrong statement with respect to biomolecules is:
**Option 3: The building block of lipids are amino acids.**

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