Which of the following does not pertain to a protostome?

Options

A. Spiral cleavage
B. Blastopore is associated with the anus
C. Schizocoelom
D. Mouth is associated with first opening

Explanation

To determine which of the following does not pertain to a protostome, we need to analyze each option based on the characteristics of protostomes:

1. **Spiral Cleavage**: This is a type of embryonic development seen in protostomes. In spiral cleavage, the cells divide in a spiral arrangement, and this type of cleavage is determinant, meaning the fate of the cells is determined early in development. Therefore, this option pertains to protostomes.

2. **Blastopore is Associated with the Anus**: In protostomes, the blastopore (the first opening that forms during the development of the embryo) becomes the mouth. In contrast, in deuterostomes, the blastopore becomes the anus. Hence, this statement does not pertain to protostomes.

3. **Schizocoelom**: This refers to a type of body cavity formation in protostomes where the coelom (body cavity) forms by the splitting of the mesoderm. This is a characteristic feature of protostomes, so this option does pertain to protostomes.

4. **Mouth is Associated with First Opening**: This statement is true for protostomes, as the first opening that forms during development becomes the mouth. Thus, this option also pertains to protostomes.

Based on this analysis, the correct answer is:

**Option 2: Blastopore is associated with the anus** does not pertain to a protostome.