Question

Which of the following is true about sub-phylum Cephalochordata?

• A. Notochord is present only in larval tail
• B. Notochord is replaced by a vertebral column in the adult
• C. Notochord extends from head to tail
• D. They are also called tunicates

Answer 1

The correct option is C Notochord extends from head to tail

Phylum Chordata is classified into three sub-phyla - Urochordata, Cephalochordata and Vertebrata. In Urochordata, notochord is present only in the larval tail, while in Cephalochordata, it extends from head to tail region and is persistent throughout life. The members of sub-phylum Vertebrata possess notochord during the embryonic period. The notochord is replaced by a cartilaginous or bony vertebral column in the adult. Tunicates is the common name of urochordates.