Question

Assertion :Most vertebrates show bilateral symmetry. Reason: The group which links vertebrates with invertebrates, Echinodermata have radial symmetry in their larva forms.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Assertion is incorrect but Reason is correct.

Answer 1

The correct option is C Assertion is correct but Reason is incorrect.

Most vertebrates show bilateral symmetry including humans. In bilateral symmetry, there is only one plane which will divide an organism into roughly mirror-image halves.

The group which links vertebrates with invertebrates is Echinodermata. Echinoderms are marine animals. These organisms have an unsegmented type of coelom. The larvae of echinoderms have bilateral symmetry. The larvae are the worm-like stage in the life cycle of the organism. During metamorphosis, there is a reorganization of the body organs. The adult form of this organisms has developed the characteristic radial symmetry. The echinoderms have five arms which are modified to form the tube feet. These arms are attached to the central disc-shaped body. This gives the organism radial form of symmetry.

Thus, the correct answer is option C.