Cockroach and earthworm have common type of

Options

A. Heart
B. Nerve cord
C. Nephridia
D. Spermathecae

Explanation

To answer the question regarding the common type of structure found in both cockroaches and earthworms, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Organ Systems**: Begin by examining the different organ systems present in both cockroaches and earthworms. This includes the circulatory system, nervous system, excretory system, and reproductive system.

2. **Circulatory System**:
- Cockroaches have a 13-chambered heart and an open circulatory system with blood vessels.
- Earthworms do not have a true heart; instead, they possess a series of aortic arches that function similarly.

3. **Nervous System**:
- Both organisms have a ventral nerve cord, but the structure and arrangement differ.
- Cockroaches have a double ventral nerve cord, while earthworms have a single ventral nerve cord.

4. **Excretory System**:
- Earthworms use nephridia for excretion.
- Cockroaches utilize Malpighian tubules for excretion, which are different structures.

5. **Reproductive System**:
- Both cockroaches and earthworms have structures for storing sperm.
- In both organisms, these structures are pouch-like and serve the same function of storing sperm.

6. **Conclusion**:
- After analyzing the various systems, it is evident that the common type of structure in both cockroaches and earthworms is the **spermatheca**. This structure is responsible for storing sperm in both species.

### Final Answer:
Cockroach and earthworm have a common type of **spermatheca**.

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