Blastopore is

Options

A. Opening of neural tube
B. Opening of gastrocel/archenteron
C. Future anterior end of embryo
D. Found in blastula.

Answer

**Step-by-Step Solution:**

1. **Definition of Blastopore**: The blastopore is an important structure that forms during the early stages of embryonic development, specifically during the process known as gastrulation.

2. **Formation During Gastrulation**: During gastrulation, the embryo undergoes significant changes, including the migration of cells. The blastopore serves as an opening that allows for the inward movement of cells, leading to the formation of the endoderm and mesoderm layers.

3. **Connection to Archenteron**: The blastopore is directly associated with the archenteron, which is the primitive gut formed during gastrulation. The archenteron will eventually develop into the digestive tract of the organism.

4. **Role in Animal Development**: In many animals, the blastopore can develop into either the mouth or the anus, depending on the type of organism. This classification divides animals into two main groups: protostomes (where the mouth develops from the blastopore) and deuterostomes (where the anus develops from the blastopore).

5. **Conclusion**: Therefore, the correct answer to the question "Blastopore is" is that it is the "opening of the gastrocele (archenteron)."

**Final Answer**: The blastopore is the opening of the gastrocele (archenteron).

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