Q. Which one of the following statements is totally wrong about the occurrence of notochord while the other three are correct
A) It is absent throughout life in humans from the very beginning
B) It is present throughout life in Amphioxus
C) It is present only in larval tail in Ascidians
D) It is replaced by a vertebral column in adult frog
Explanation
[Solution from source] All chordates, humans included, have a notochord at some stage; in humans it forms in the embryo and is later replaced by the vertebral column, so saying it is absent from the very beginning is totally wrong. Amphioxus keeps it throughout life, ascidians have it only in the larval tail and in frogs it is replaced by the vertebral column. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.