The basic event of development in higher organisms is

TLS Online TPP Program

#Question id: 8929

#Unit 9. Diversity of Life Forms

An obsolete taxon, the ʺRadiata,ʺ included all phyla whose adults had true radial symmetry. Today, the ʺRadiataʺ is more correctly considered to be

1. a clade.

2. a grade.

3. monophyletic.

4. paraphyletic.

5. polyphyletic.

TLS Online TPP Program

#Question id: 8930

#Unit 9. Diversity of Life Forms

Soon after the coelom begins to form, a researcher injects a dye into the coelom of a deuterostome embryo. Initially, the dye should be able to flow directly into the

TLS Online TPP Program

#Question id: 8931

#Unit 9. Diversity of Life Forms

A researcher is trying to construct a molecular-based phylogeny of the entire animal kingdom. Assuming that none of the following genes is absolutely conserved, which of the following would be the best choice on which to base the phylogeny?

TLS Online TPP Program

#Question id: 8932

#Unit 9. Diversity of Life Forms

What is the correct sequence of the following four events during an animalʹs development?

1. gastrulation

2. metamorphosis

3. fertilization

4. cleavage

TLS Online TPP Program

#Question id: 8933

#Unit 9. Diversity of Life Forms

At which developmental stage should one be able to first distinguish a diploblastic embryo from a triploblastic embryo?

TLS Online TPP Program

#Question id: 8934

#Unit 9. Diversity of Life Forms

At which developmental stage should one be able to first distinguish a protostome embryo from a deuterostome embryo?