Cyclostomata have an elongated body bearing 6-15 pairs of gill slits which help in
Respiration
digestion
Excretion
All of these
As we have learned
Body of Cyclostomata -
Elongated body bearing 6 - 15 pairs of gills slits for respiration.
- wherein
Cranium and vertebral column are cartilaginous and with persistent notochord.