Question

What is the fate of notochord in an adult organism which belongs to Gnathostomata?

• A. Notochord extincts
• B. Notochord is replaced by the vertebral column
• C. Notochord becomes vestigial
• D. Notochord continues same as in larval stage

Answer 1

Answer: (B)

Notochord is replaced by the vertebral column

• Phylum Chordata can be divided into two categories:-

1) Protochordata- The notochord is present in the larval stage of these animals and it is rudimentary in adults.

2) Vertebrata- The notochord is replaced by a vertebral column in adults.

• Gnathostomata is a superclass which includes jawed vertebrate fishes.
  
• They come under the subphylum vertebrata i.e the notochord is replaced by a vertebral column in adults.
• So, the correct answer is 'Notochord is replaced by the vertebral column'.