Ivy Tech Online Biology: Session 7

The evolution of population due to chance is

genetic drift

In a population with brown and green alleles for color, genetic drift

has more effect on the evolution of a small population

________ speciation is the process by which two populations of a single species become two species following a geographic separation

Allopatric

_______ nomenclature is the system of naming organisms by their genus and species

Binomial

In a species of snail, dark-shelled individuals are better hidden from bird predators in the shady forest, while light-shelled individuals are better hidden in well-lit brushy edge areas. If there were no areas of intermediate brightness in this habitat, which type of selection would act on shell color in these snails?

Disruptive Selection

A _______ is a structure that resembles one found in a different species, but results from convergent evolution rather than shared ancestry

analogy

A _______ is a common structure in different species that results from a shared ancestry

homology

_______ is the general term for the process by which new species form

polyplodiSpeciation

The condition in which one or more entire sets of chromosomes have been added to the genome of a diploid organism is known as _____

polyploidy

Color is an inherited trait in beetles. If brown beetles move into a population from a nearby island, which of the following statements is correct?

Gene flow causes the frequency of the brown allele to increase.

Remember that color is an inherited trait in beetles. Which of the following is an example of natural selection?

Green beetles leave more offspring than brown beetles because they re better at finding food.

Small lizards have difficulty defending their territory, but large lizards are more likely to be preyed upon by owls. Which type of selection would act on body size in these lizards under these conditions?

Stabilizing selection

_______ speciation is the process by which two populations of a single species that share the same geographical area become two separate species.

Sympatric

A subset of a population of birds leaves its habitat and colonizes a nearby island. After many generations, the island sinks and the population of birds living on the island returns to its original habitat. Which of the following statements most accurately describes the two bird populations?

The birds were separated by dispersal

If color is an inherited trait in beetles, and birds are more likely to eat brown beetles than green beetles,

the frequency of the green allele will increase

Reproductive isolating mechanisms keep species from interbreeding in one of two ways _______ isolating mechanisms are geographical barriers that prevent contact between species; _____ isolating mechanisms are differences in anatomy, physiology, or behavior that prevent mating between species.

Extrinsic, intrinsic

True or False. In the example described in the tutorial, the red amoebas survived the catastrophic event, and all future generations of amoebas were red because the red amoebas had a higher reproductive rate than the blue ones.

False

Which of the following events could NOT be caused by a population bottleneck?

Increased population size

Which of the following statements about the amoeba population described at the end of the tutorial is true?

It is more vulnerable to extinction due to lack of genetic variation.

Which of the following statements about reinforcement is true?

Reinforcement is a type of natural selection.