Q156 (2024)
The toxin proteins isolated from Bacillus thuringiensis, coded by which of the following genes would control cotton bollworms and corn borer, respectively?
- cryIAc and cryIIIAb
- crylAc and cryIIAb
- crylAc and crylAb
- cryIIAb and crylAc
### Related Formula
$\begin{aligned}
\text{Cotton Bollworms} &\rightarrow cryIAc \text{ and } cryIIAb\\
\text{Corn Borer} &\rightarrow cryIAb
\end{aligned}$
### Core Logic
The specific Bt toxin genes encoded by *Bacillus thuringiensis* are insect group specific:
* Genes $cryIAc$ and $cryIIAb$ control cotton bollworms.
* Gene $cryIAb$ controls corn borer.
Therefore, for cotton bollworms and corn borer respectively, the genes are $cryIAc$ and $cryIAb$.
### Step 1: Option Matching
Matches with Option (3): $cryIAc$ and $cryIAb$.
### Pattern Recognition
Sees: "cotton bollworms and corn borer genes".
Shortcut: Cotton bollworm = $cryIAc$/$cryIIAb$; Corn borer = $cryIAb$.
### Evaluation Rubric / Model Answer
null
### Chapter Mix
Class 12 Biology: Biotechnology and its Applications
