Field observation suggests that populations of a particular species of herbivorous mammal undergo cyclic fluctuations in  density  at  three-  to  five-year  intervals.  Which  of  the  following  represent  (a)  plausible  explanation(s)  of  these cycles?

TLS Online TPP Program

#Question id: 8927

#Unit 9. Diversity of Life Forms

Arthropods invaded land about 100 million years before vertebrates did so. This most clearly implies that

TLS Online TPP Program

#Question id: 8928

#Unit 9. Diversity of Life Forms

An adult animal that possesses bilateral symmetry is most certainly also

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