Question

What is the characteristic of notochord in Cephalochordata?

• A. It extends along the length of the body.
• B. It is restricted to head region.
• C. It is restricted to body excluding the head region.
• D. It is present along the length in larva but restricted to head region in adult.

Answer 1

The correct option is B It is restricted to head region.

Cephalochordates are Urochordates are marine organisms.

In the members of the cephalochordates, the notochord is persistent and present throughout the body. In case of the members of the Urochordates, the notochord is present in posterior half of the body of the organism. Therefore, the organisms in the two groups are divided on the basis of the length of notochord. The cephalochordates are the closest relatives of the vertebrates.

Thus, the correct answer is option B.