Exam 5 Material (Protosomes)

Question 1

How big is the protosome group?

Answer 1

largest group of animals

Question 2

Is the protosome group monophyletic?

Answer 2

Yes, the group is monophyletic

Question 3

Are protosomes diploblastic or triploblastic?

Answer 3

They are triploblastic (have endoderm, ectoderm, and mesoderm)

Question 4

What kind of symmetry do protosomes have?

Answer 4

Bilateral symmetry

Question 5

What do all protosomes have?

Answer 5

Coelom/body cavity (however, there are a few exceptions)

Question 6

What kind of cleavage do protosomes have?

Answer 6

determinant cleavage (when the cells divide, they stack in a spiral manner and cells have “predetermined fates”—they are going to be at certain parts of their bodies)

Question 7

Under pressure, what can act as a hydrostatic skeleton (acts as a solid structure)?

Answer 7

Coelom

Question 8

What allows organs to move independent of the outer body/can be used for storing things (ex: reproductive structures)?

Answer 8

Coelom

Question 9

Protosomes can be divided into what two major clades/classes?

Answer 9

Lophotrochozoa and endysozoa