Amphids for olfacto-reception are present in Ascaris on

Options

A. Pre-anal papilla
B. Post-anal papilla
C. Dorsal lip
D. Ventrolateral lips

Answer

To answer the question regarding the location of amphids for olfactory reception in Ascaris, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Function of Amphids**:
- Amphids are specialized sensory structures in nematodes (roundworms) that are involved in olfactory (chemical) reception.

2. **Identify the Location of Amphids in Ascaris**:
- In Ascaris, amphids are located in the mouth region.

3. **Examine the Mouth Structure of Ascaris**:
- The mouth of Ascaris is triangular and consists of three lips: one dorsal lip and two ventral lips.

4. **Determine the Role of Each Lip**:
- The dorsal lip is primarily responsible for taste reception.
- The two ventrolateral lips are responsible for olfactory reception.

5. **Analyze the Given Options**:
- The options provided are:
- A) Pre-anal papilla
- B) Post-anal papilla
- C) Dorsal lip
- D) Ventral lateral lip
- Since amphids for olfactory reception are located on the ventrolateral lips, we can eliminate options A and B, as they are not related to the mouth region.

6. **Select the Correct Answer**:
- Given that the ventrolateral lips are responsible for olfactory reception, the correct answer is **D) Ventral lateral lip**.

### Final Answer:
The amphids for olfactory reception are present in Ascaris on the **ventral lateral lip**.