2025 Animal KingdomPhylum Chordata Classification Easy Question 11 of 123 in Animal Kingdom

Assertion (A): All vertebrates are chordates but all chordates are not vertebrate.

Reason (R): The members of subphylum vertebrata possess notochord, during the embryonic period, the notochord is replaced by a cartilaginous or bony vertebral column in adults.
A Both A and R are true and R is the correct explanation of A
B Both A and R are true but R is not the correct explanation of A
C A is true but R is false
D A is false but R is true

The answer is A.

Solution

All vertebrates belong to phylum Chordata, but protochordates lack a vertebral column; in vertebrates, the embryonic notochord is replaced by a vertebral column.

Phylum Chordata includes non-vertebrate protochordates (Urochordata and Cephalochordata) where the notochord is not replaced by a backbone. In subphylum Vertebrata, the embryonic notochord is replaced by a cartilaginous or bony vertebral column, making R the exact explanation of A.

Concept Chordate vs Vertebrate

Animal Kingdom in past papers

123 questions from this chapter have appeared across 27 exam years.