Question

All vertebrate are chordates ,but all chordates are not vertebrate justify the stetments

Answer 1

See first i will explain u the major characters of chordate. They are as follows:-
1) Having NOTOCHORD (a major character)
2) Presence of PHARYNGEAL GILL SLITS
3) Having VERTEBRAL COLUMN and
4) DORSALLY PLACED NERVE CORD.
so as presence of vertebral is the character of chordate. Therefore every chordate show vertebral column.
But there are some primitive chordate who does not have vertebral column in them buttt they show other 3 characters of the chordate so they are considered as chordate.
Like this there are some species who dont have vertebrate but are chordate due to presence of other chordate characters.

**HOPE THAT IT WAS HELPFULL AND U HAVE CLEAR YOUR CONCEPT**

Answer 2

All vertebrates are chordates but all chordates are not vertebrates justify the statement

Answer => members of subphylum vertebrate possess notochord during the embryonic period.thus notochord is being replaced by bony vertebral colum in adults