Please help!!!!! You collected a marine sediment sample that contained mysteriou
ID: 253370 • Letter: P
Question
Please help!!!!!
You collected a marine sediment sample that contained mysterious zygotes of uncertain origin. Curious, you brought them home to your lab and periodically observed the development of the larvae. * You watched them go through spiral cleavage. . You watched them go through gastrulation, and subsequent development of a secondary opening. . The blastopore developed into the mouth. * You watched in awe as the embryo formed its coelom via schizocoely At last, the little beast became a trochophore which then developed into a swimming veliger with a tiny, spiral shell. * As it grew, it LOST its shell and finally developed into an adult that looked like this: To which taxa does this little beast belong? (Write down all that apply to get credit!) a. Platyhelminthes b. Acoela c. Mollusca d. Lophotrochozoa e. Cephalopoda f. Bivalvia g. GastropodaExplanation / Answer
Sample belongs to mollusca.
Mollusca shows spiral clevage where cleavage furrow goes through an obique angel. This type of cleavage is responsible for torsion of shell.
Except Echionodermata, rest all invertebrates are protostome type means first opening formed due to gastruation acts as mouth.
During the developmental events larva of mollusca passes through trocophore and veliger larval stages.
Schizocoely is formed during larval stage often get reduced in adult stage and form a cavity that surrounds only heart.