Which on of the following statement is incorrect for carboxylating enzyme in `C_(3)` plants

Options

A. Bifuncational nature
B. Can bind with `CO_(2)` only
C. Its old name was carboxydismutase
D. Located is stroma or matrix chloroplasta

Answer

To determine which statement is incorrect regarding the carboxylating enzyme in C3 plants, we will analyze each option provided:

1. **Bifunctional nature**: The enzyme involved in the carboxylation process in C3 plants is Rubisco (Ribulose bisphosphate carboxylase/oxygenase). This enzyme is indeed bifunctional, as it can catalyze both the carboxylation of ribulose bisphosphate (RuBP) with CO2 and the oxygenation of RuBP with O2. Therefore, this statement is **correct**.

2. **Can bind with CO2 only**: While Rubisco primarily binds with CO2 during the carboxylation process, it can also bind with O2, leading to a different reaction (photorespiration). Hence, this statement is **incorrect** because it implies exclusivity to CO2 binding.

3. **Its old name was carboxy-dismutase**: This statement is also **incorrect**. The enzyme Rubisco has been mistakenly referred to as carboxydismutase in the past, but this is not its correct historical name. The confusion arises from the enzyme's functions, but the correct name is Rubisco.

4. **Located in stroma or matrix of chloroplasts**: This statement is **correct**. Rubisco is located in the stroma of chloroplasts, where the Calvin cycle occurs.

Based on the analysis above, the incorrect statement regarding the carboxylating enzyme in C3 plants is:

**Answer: Option 2 - "Can bind with CO2 only" is incorrect.**