The inactive protoxin is activated in the gut of the insect by :

Options

A. acidic pH
B. alkaline pH
C. low temperrature
D. high temperature

Answer

To solve the question regarding how the inactive protoxin is activated in the gut of the insect, we can follow these steps:

### Step 1: Understand the Concept of Protoxin
- **Protoxin** is the inactive form of a toxin produced by certain bacteria, such as Bacillus thuringiensis (Bt). It needs to be activated to exert its toxic effects.

### Step 2: Identify the Activation Process
- The activation of protoxin occurs when it is ingested by an insect. The environment within the insect's gut plays a crucial role in this activation.

### Step 3: Analyze the Conditions in the Insect Gut
- The gut of the insect has a specific pH level. It is important to determine whether this pH is acidic, alkaline, or neutral.

### Step 4: Determine the Correct pH Level
- Research indicates that the gut of many insects, particularly those targeted by Bt, is alkaline. This alkaline environment is essential for the conversion of protoxin to its active form.

### Step 5: Eliminate Incorrect Options
- The other options provided (acidic pH, low temperature, and high temperature) do not facilitate the activation of protoxin in the insect gut. Acidic conditions would not activate the protoxin, and temperature changes do not play a significant role in this specific activation process.

### Conclusion
- Based on the understanding that the alkaline pH in the insect gut activates the protoxin, the correct answer to the question is **B. Alkaline pH**.

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