Discussion
Adult of urochordates are highly specialized having lost the following characteristics except :
Answer: B
The feature adult urochordates keep is the siphon.
The tunicate larva is a free-swimming tadpole with a notochord in its tail and a dorsal hollow nerve cord, the chordate features that place the group in the phylum. At metamorphosis the larva attaches by its front end and becomes a sac-like filter feeder. The tail with its notochord is absorbed, and the nerve cord is reduced to a single ganglion. The adult draws water in through an incurrent (oral) siphon and passes it out through an excurrent (atrial) siphon.
So the notochord and the nerve cord (spelt chord in the paper) are lost, and urochordates have no true coelom; its place is taken by the atrial cavity. The siphons are the one listed feature present in the adult.
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development