Calcium:
(a) maintain cell permeability
(b) stabilize structure of chromosome
(c ) is component of Rubisco

Options

A. Only (a) is correct
B. Only b is correct
C. Only c is correct
D. a and b are correct

Answer

To answer the question regarding the role of calcium in plants, we will analyze each statement provided:

**Step 1: Analyze Statement (a) - "Calcium maintains cell permeability."**
- Calcium plays a crucial role in maintaining the structural integrity of cell membranes. It helps in stabilizing the membrane structure, which is essential for regulating the movement of substances in and out of the cell. Thus, this statement is **correct**.

**Step 2: Analyze Statement (b) - "Calcium stabilizes the structure of chromosomes."**
- Calcium ions are involved in the formation of the mitotic spindle, which is essential during cell division. The mitotic spindle helps in the proper segregation of chromosomes. Therefore, calcium does contribute to stabilizing the structure of chromosomes during cell division, making this statement **correct**.

**Step 3: Analyze Statement (c) - "Calcium is a component of Rubisco."**
- Rubisco (Ribulose-1,5-bisphosphate carboxylase/oxygenase) is an enzyme critical for photosynthesis. However, calcium is not a component of Rubisco. Rubisco is primarily composed of proteins and does not require calcium for its structure. Therefore, this statement is **incorrect**.

**Conclusion:**
Based on the analysis:
- Statement (a) is correct.
- Statement (b) is correct.
- Statement (c) is incorrect.

Thus, the correct answer is that statements (a) and (b) are true regarding the role of calcium in plants, while statement (c) is false.

**Final Answer:**
The correct options are (a) and (b) only.

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