Similarity between Echinoderms and Chorodates is

Options

A. deuterostomatic: tube-within-a tube plan
B. protostomatic, tube-within-a-tube plan
C. water vascular system
D. kidneys

Answer

### Step-by-Step Solution:

1. **Identify the Organisms**:
- Echinoderms (e.g., sea stars, sea urchins) and Chordates (e.g., humans, fish) are two distinct groups of animals.

2. **Determine the Classification**:
- Both Echinoderms and Chordates belong to the group known as Deuterostomes. This classification is based on their embryonic development.

3. **Understand the Developmental Features**:
- In Deuterostomes, the blastopore (the first opening that forms during embryonic development) develops into the anus, while in Protostomes (another group of animals), it develops into the mouth.

4. **Recognize Symmetry**:
- Both groups exhibit bilateral symmetry at some stage of their life cycle. This means their body can be divided into two mirror-image halves.

5. **Cleavage Type**:
- Both Echinoderms and Chordates exhibit radial cleavage during their early development. Radial cleavage means that the cells divide in a way that is symmetrical around the axis of the embryo.

6. **Conclusion**:
- The primary similarity between Echinoderms and Chordates is that they are both Deuterostomes, which is characterized by their embryonic development, bilateral symmetry, and radial cleavage.

### Final Answer:
The similarity between Echinoderms and Chordates is that they are both Deuterostomes.

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