Question

Assertion : Branchiostoma and Balanoglossus are bilaterally symmetrical and triploblastic animals.
Reason : They are exclusively marine and possess notochord.

• A. If both assertion and reason are true and reason is the correct explanation of assertion
• B. If both assertion and reason are true but reason is not the correct explanation of assertion
• C. If assertion is true but reason is false
• D. If both assertion and reason are false

Answer 1

Answer: (C)

Balanoglossus (Phylum-Hemichordata) and Branchiostoma (= Amphioxus, Subphylum - Cephalochordata) both are bilaterally symmetrical and triploblastic animals. Both are marine animals. Balanoglossus does not possess a notochord whereas Branchiostoma being a chordate possesses notochord that persists throughout life.