Which of the following structure is/are not present in the male
genital part of a cockroach ?
(i) Ejaculatory duct (ii) Vasa differentia (iii) seminal vesicle (iv) Vestibulum (v) Phallomere

Options

A. i,ii, iii,iv,v
B. i iii only
C. Only iv
D. i , iii, iv,v

Answer

To solve the question regarding which structures are not present in the male genital part of a cockroach, we will analyze each of the given options one by one.

### Step-by-Step Solution:

1. **Ejaculatory Duct**:
- The ejaculatory duct is a structure that plays a role in the ejaculation of semen from the male cockroach. It is indeed part of the male genital system.
- **Conclusion**: Present in male genital part.

2. **Vasa Differentia**:
- The vasa differentia are tubes that connect the testes to the seminal vesicles. They are essential for transporting sperm.
- **Conclusion**: Present in male genital part.

3. **Seminal Vesicle**:
- Seminal vesicles are responsible for storing and maturing sperm before ejaculation. They are a crucial part of the male reproductive system in cockroaches.
- **Conclusion**: Present in male genital part.

4. **Vestibulum**:
- The vestibulum is not a part of the male genital system. It is generally associated with the female reproductive system in cockroaches.
- **Conclusion**: Not present in male genital part.

5. **Phallomere**:
- Phallomeres are structures that are part of the male genitalia in cockroaches. They have a role in the reproductive process.
- **Conclusion**: Present in male genital part.

### Final Answer:
Based on the analysis above, the structure that is **not present** in the male genital part of a cockroach is:
- **(iv) Vestibulum**