Answer :

Prochordates:

i. Prochordates are considered as the development of vertebrata.


As they do not have brain, hence they are referred as Acrania.


ii. These are divided into three sub-pylums which are Hemichordata, Cephalochordata and Urochordata.


iii. The three sub-phylums are classified on the basis of notochord.


Hemichordata


i. These are marine organisms.


ii. They do not have backbones.


iii. The body is soft, bilateral symmetrical and unsegmented.


iv. The notochord is persistent as the stomochord in the anterior region of the animal.



Balanoglossus


Cephalochordata


i. These are small fish.


ii. These are marine organisms with unpaired dorsal fin.


iii. The persistent notochord extends forward beyond the brain.



Amphioxus


Urochordata


i. The adults are mostly degenerate, and are sessile forms.


ii. The body is enveloped by a tunic or test.


iii. In Urochordata the notochord is confined to the tail region of the larva.



Ascidian


Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
caricature
view all courses
RELATED QUESTIONS :

Which is not a feTamilnadu Board Science

On the basis of PTamilnadu Board Science

Outline the flow Tamilnadu Board Science

What are the sub-Tamilnadu Board Science

Assertion :The prTamilnadu Board Science

Describe the charTamilnadu Board Science

What is acrania?<Tamilnadu Board Science

Find the missing Tamilnadu Board Science

Choose the correcTamilnadu Board Science

The animal withouTamilnadu Board Science