While sampling marine plankton in a lab, a student encounters large numbers of fertilized eggs. The student rears some of the eggs in the laboratory for further study and finds that the blastopore becomes the mouth. The embryo develops into a trochophore larva and eventually has a true coelom. These eggs probably belonged to a(n)
A) chordate.
B) echinoderm.
C) mollusc.
D) nematode.
E) arthropod.

Question

Quizplus · Accepted Answer

The presence of a trochophore larva and a true coelom are characteristic of molluscs. Additionally, in many molluscs, the blastopore becomes the mouth during embryonic development.

While Sampling Marine Plankton in a Lab, a Student Encounters