1) The biological species concept is based on:

A) differences among populations.

B) geographic isolation.

C) reproductive isolation.

D) DNA sequences.

2) The biological species concept cannot be applied to bacteria because:

A) their DNA is too similar.

B) their features are too small to be able to distinguish one kind from another.

C) they do not reproduce sexually.

D) they never exchange genes that would allow for speciation.

3) Which of these definitions of species most closely fits the biological species concept?

A) For asexually reproducing organisms, members of the same species are based on DNA and RNA base sequence analysis.

B) Members of the same species look almost exactly alike.

C) Members of the same species are all morphologically similar.

D) Members of the same species can mate and produce fertile offspring.

4) Interbreeding two different species of lovebirds produces offspring unable to build a nest after they mature because they lack the innate knowledge needed to carry the nesting materials. The hybrid offspring do not reproduce, and this limits genetic mixing of the two species. This is an example of:

A) sympatric speciation.

B) gametic inviability.

C) behavioral isolation.

D) hybrid infertility.

5) A population of mountain-dwelling salamanders migrates and splits into two populations separated by a valley they can not cross. The speciation process that may occur is:

A) allopatric.

B) temporal.

C) behavioral.

D) sympatric.

6) A population becomes isolated from other populations of the same species, and then genetic divergence occurs that prevents them from breeding with other populations. What has happened?

A) speciation

B) formation of genetic drifts

C) directional selection

D) mechanical incompatibility

7) Two different species of pines release their pollen at different times. This is an example of:

A) behavioral isolation.

B) geographic isolation.

C) mechanical isolation.

D) temporal isolation.

8) Which of these is not gametic isolation?

A) Female stigma destroys germinating pollen grain.

B) Lily sperm cannot fertilize tulip eggs.

C) Pollen grain does not germinate on stigma (female structure).

D) Male and female sex organs do not fit together.

9) The Great Dane and Chihuahua are both domestic dogs, the same species. However, mating between them is limited by:

A) behavioral isolation.

B) heterozygote disadvantage.

C) mechanical incompatibility.

D) hybrid infertility.

10) The many species of tree frogs that inhabit forests in the eastern United States maintain their genetic isolation from other species by several mechanisms, including “singing” slightly different songs. Which type of isolating mechanism does this represent?

A) temporal isolation

B) behavioral isolation

C) ecological isolation

D) mechanical isolation