Biology Study Guide: How Populations Evolve

Study Guide Biology Chapter 13 How Populations Evolve

Key Terms to Know: artificial selection balancing selection biogeography bottleneck effect directional selection disruptive selection evolution evolutionary tree fossil record fossils founder effect frequency-dependent selection gene flow gene pool genetic drift
Hardy-Weinberg principle heterozygote advantage homologous structures homology microevolution molecular biology natural selection paleontologist population relative fitness sexual dimorphism sexual selection stabilizing selection strata vestigial structures

Good review questions from the “Testing Your Knowledge” section at the end:
#’s 13, 14

Exam questions are similar, but not exactly like these:
One of the major sources of evidence for evolution is in the comparative anatomy of organisms. Features that look different but have similar structural origin are called
A. Homologous structures.
B. Analogous structures.
C. Vestigial structures.
D. Equivalent structures.

Darwin proposed that individuals with traits that help them live in their immediate environment tare more likely to survive and reproduce than individuals without those traits. He called this
A. Natural selection.
B. arithmetic progression.
C. The theory of evolution.
D. geometric progression.

Darwin was greatly influenced by Thomas Malthus who observed that
A. Food supplies increase geometrically.
B. Populations increase arithmetically.
C. populations are capable of geometric increase, yet remain at constant levels.
D. the food supply usually increases faster than the population that depends on it.

Selection that causes one extreme phenotype to be more frequent in a population is an example of
A. Disruptive selection.
B. Stabilizing selection.
C. Directional selection
D. Equivalent selection.

The flipper of a dolphin and the fin of a tuna are
A. Homologous structures.
B. Analogous structures.
C. Vestigial structures.
D. Reciprocal structures.

The northern elephant seal went through a severe population decline as a result of hunting in the late 1800s. As a result of a hunting ban, the population has rebounded but is now homozygous for nearly every gene studied. This is the result of
A. Mutation
B. Natural selection
C. Founder effect
D. Bottleneck
E. Gene flow

A small, reproductively isolated religious sect called the Dunkers was established by 27 families that came to the US from Germany 200 years ago. The frequencies for blood group alleles in this population differ significantly from those in the general US population. This is the result of
A. Mutation
B. Natural selection
C. Founder effect
D. Bottleneck
E. Gene flow

Within a population, plants that produce an insect toxin are more likely to survive and reproduce than plants that do not produce the toxin. This is the result of
A. Mutation
B. Natural selection
C. Founder effect
D. Bottleneck
E. Gene flow

The gene pool of a population of bighorn sheep in the southwest US is altered when several animals cross over a mountain pass and join the population. This is the result of
A. Mutation
B. Natural selection
C. Founder effect
D. Bottleneck
E. Gene flow

During his voyage around the world, Charles Darwin was inspired to think about evolution by.
A. books that he read.
B. fossils that he collected.
C. studying adaptations of organisms to their environments.
D. unique organisms he saw in the Galápagos Islands.
E. all of the above.

Breeding of plants and animals by humans is called
A. natural selection.
B. sexual recombination.
C. founder effect.
D. artificial selection.
E. neutral variation.

Which of the following generates variation within a population?
A. natural selection
B. genetic drift
C. mutation
D. A & B
E. B & C

Which of the following results in adaptation to the environment?
A. natural selection
B. mutation
C. genetic drift
D. recombination
E. founder effect

The smallest unit that can evolve is a
A. species.
B. genotype.
C. gene.
D. population.
E. individual.

The ultimate source of all genetic variation is
A. natural selection.
B. genetic drift.
C. sexual recombination.
D. the environment.
E. mutation

Organisms that possess homologous structures probably
A. are headed for extinction.
B. evolved from the same ancestor.
C. have increased genetic diversity.
D. by chance had similar mutations in the past.
E. are not related.

Sexual recombination occurs when chromosomes are shuffled in __________.
A. mitosis.
B. genetic drift.
C. natural selection.
D. mutation.
E. meiosis.

Darwin
A. was the first person to conceive that organisms could change over time.
B. believed that organisms could pass on acquired changes to offspring.
C. was eager to publish his theory so that he could get all the credit.
D. worked out the mechanisms of evolution—natural selection.
E. was the first to realize that fossils are remains of ancient life.

In a population of black bears, which would be considered the fittest?
A. the biggest bear B. the bear having the largest number of mutations C. the bear that blends in with its environment the best D. the strongest, fiercest bear E. the bear that leaves the most descendants

Blue poppies native to China are grown at a plant-breeding center in California, where those with the thickest leaves survive and reproduce best in the drier climate. This evolutionary adaptation of the poppies to their new environment is due to
A. Genetic drift.
B. Stabilizing selection.
C. Directional selection.
D. Neutral variation.
E. Disruptive selection.

Which of the following would result in evolutionary adaptation of a mouse population to its environment?
A. Half the mice are killed by an avalanche.
B. A mutation for spotted fur occurs.
C. Several mice leave the area and mate with individuals elsewhere.
D. Mice with thicker fur best survive a cold winter.
E. Mice are most likely to mate with close neighbors.

Each of us is part of the ongoing evolution of the human species. Which of the following occurrences would have the greatest impact on the future biological evolution of the human population?
A. You work out every day so that you stay physically fit and healthy.
B. A mutation occurs in one of your skin cells.
C. You move to Hawaii, the state with the longest life expectancy.
D. A mutation occurs in one of your sperm or egg cells.
E. You encourage your children to develop their intellectual abilities.

Natural selection is sometimes described as “survival of the fittest.” Which of the following best measures an organism’s fitness?
A. How strong it is when pitted against others of its species.
B. How many fertile offspring it produces.
C. Its mutation rate.
D. How much food it is able to make or obtain.
E. Its ability to withstand environmental extremes.

________ and ________ generate variation, while ________ results in adaptation to the environment.
A. Genetic drift … natural selection … mutation
B. Mutation … sexual recombination … natural selection
C. Overproduction of offspring …mutation … sexual recombination
D. Natural selection … mutation … sexual recombination
E. Sexual recombination … natural selection … mutation

Which of the following did not influence Darwin as he synthesized the theory of evolution by natural selection?
A. Examples of artificial selection that produce large and relatively rapid changes in domesticated species
B. Lyell’s Principles of Geology, on gradual geologic changes
C. Comparisons of fossils with living organisms
D. The biogeographic distribution of organisms, such as the unique species on the Galápagos Islands
E. Mendel’s paper describing the laws on inheritance

In an area of erratic rainfall, a biologist found that grass plants with alleles for curled leaves reproduced better in dry years, and plants with alleles for flat leaves reproduced better in wet years. This situation would tend to _______.
A. Cause genetic drift in the grass population
B. Preserve genetic variation in the grass population
C. Lead to stabilizing selection in the grass population
D. Lead to uniformity in the grass population
E. Cause gene flow in the grass population

Which of the following pairs of structures is least likely to represent homology?
A. The hemoglobin of a human and that of a baboon
B. The mitochondria of a plant and those of an animal
C. The wings of a bird and those of an insect
D. The tail of a cat and that of an alligator
E. The foreleg of a pig and the flipper of a whale

Darwin’s claim that all life is descended from a common ancestor is best supported with evidence from _________.
A. The fossil record.
B. Molecular biology.
C. Evolutionary trees.
D. Comparative anatomy.
E. Comparative embryology.

Within a few weeks of treatment with the 3TC for the HIV virus, a patient’s HIV population consists entirely of 3TC-resistance viruses. How can this result best be explained?
A. HIV can change its surface proteins and resist vaccines.
B. The patient must have become reinfected with a resistant virus.
C. A few drug-resistant viruses were present at the start of treatment, and natural selection increased their frequency.
D. The drug caused the HIV genes to change.
E. HIV began making drug-resistant versions of its enzymes in response to the drug.

Of the following possibilities, the best way to estimate an organism’s evolutionary fitness is to measure the
A. Size of its offspring
B. Number of eggs it produces
C. Number of eggs it produces over its lifetime
D. Number of offspring it produces over its lifetime
E. Number of offspring it produces over its lifetime that survive to breed

In many species of fireflies, males flash to attract females. Each species has a different flashing pattern. This is probably an example of
A. Ecological isolation
B. Temporal isolation
C. Geographical isolation
D. Postzygotic isolation

After the demise of the dinosaurs, mammals evolved rapidly into many new forms because of
A. The founder effect
B. A genetic bottleneck
C. Adaptive radiation
D. Geological time
E. Genetic drift