Question

what is the meaning of notochord?

Answer 1

Notochord is  found only in phylum Chordata. It is a primitive beginning to the vertabrate column( backbone), it is fexible rod like structure that arisesfrom cells of mesoderm

Answer 2

i) Notochord is a long rod like supporting structure present on the dorsal side of animal body.

ii) It keeps the nerve tissue isolated from the remaining body.

iii) It provides place for the muscles to attach for ease of moments.

iv) Animals which do not have notochord are called non chordates.

v) In hemichordates, notochord is present in proboscis region only.

vi) In chordates, notochord is present in the body during any developmental stage.

vii) In Urochordates, it is present only in tail region of larvae.

viii) In Cephalochordates, notochord is present throughout the body length.

ix) In vertrebrates, notochord is replaced by vertebral column.