A) pelagic
B) free - swimming
C) planktonic
D) sessile
Correct Answer: D
Solution :
Sponges are asymmetrical, but some show radial symmetry. Mostly they are marine and sessile (attached to substratum). They contain flagella in their colar cells (choanocytes) linning the body cavity (spongocoel) and thus set up water current. These cells were discovered by James Clarke.
You need to login to perform this action.
You will be redirected in
3 sec
