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A: True coelom originated for the first ...

A: True coelom originated for the first time in phylum annelida.
R: It allowed the animal to have an alimentary canal longer than the body & space for storing gametes.

A

If both assertion & reason are true and the reason is the correct explanation of the assertion, then mark (1).

B

If both assertion & Reason are true but the reason is not the correct explanation of the assertion, them mark (2).

C

If assertion is true statement but reason is false, them mark (3).

D

If both assertion and reason are false statements, them mark (4).

Text Solution

AI Generated Solution

The correct Answer is:
**Step-by-Step Solution:** 1. **Understanding the Assertion (A)**: The assertion states that "True coelom originated for the first time in phylum Annelida." - True coelom refers to a body cavity that is completely lined by mesoderm. This is a significant evolutionary development in the animal kingdom. 2. **Evaluating the Assertion**: The statement is indeed true. Annelids, which include earthworms and leeches, are the first group of animals to exhibit a true coelom. This distinguishes them from other phyla that may have a pseudocoelom or no body cavity at all. 3. **Understanding the Reason (R)**: The reason states that "It allowed the animal to have an alimentary canal longer than the body & space for storing gametes." - An alimentary canal is a digestive tract that runs from the mouth to the anus, and having a longer canal can improve digestion and nutrient absorption. 4. **Evaluating the Reason**: This statement is also true. The presence of a true coelom does allow for a more complex body structure, which includes a longer alimentary canal and space for reproductive organs, thus facilitating the storage of gametes. 5. **Determining the Relationship**: While both statements are true, the reason provided does not directly explain why the true coelom originated in Annelida. The assertion is about the evolutionary development of the coelom, while the reason discusses the advantages of having a coelom, which is a different aspect. 6. **Conclusion**: Therefore, the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion. This leads us to conclude that the answer is option B. ---
**Step-by-Step Solution:** 1. **Understanding the Assertion (A)**: The assertion states that "True coelom originated for the first time in phylum Annelida." - True coelom refers to a body cavity that is completely lined by mesoderm. This is a significant evolutionary development in the animal kingdom. 2. **Evaluating the Assertion**: The statement is indeed true. Annelids, which include earthworms and leeches, are the first group of animals to exhibit a true coelom. This distinguishes them from other phyla that may have a pseudocoelom or no body cavity at all. 3. **Understanding the Reason (R)**: The reason states that "It allowed the animal to have an alimentary canal longer than the body & space for storing gametes." ...
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