Which of the following terms represents the frequency of heterozygotes in a population that is in Hardy-Weinberg equilibrium?
An antibiotic kills 99.9% of a bacterial population. You would expect the next generation of bacteria
to be more resistant to that antibiotic.
The role of a control in an experiment is to
provide a basis of comparison to the experimental group.
Humans share several features with salamanders. Certain genes and proteins are nearly identical
between the two species; both species have four limbs with a similar skeletal structure; the
species' early embryos are very similar; and where the salamander has a functional tail, humans
have a vestigial tailbone. In evolutionary terms, these are examples of
Large antlers in male elk, which are used for battles between males, are a good example of a trait
Microevolution, or evolution at its smallest scale, occurs when
a population's allele frequencies change over a span of generations.
A systematist includes a lizard in a phylogenetic analysis of relationships among bird families.
In this analysis, the lizard would be treated as
Which of the following options lists taxonomic categories in the correct order from most specific
to most general?
genus, family, order, class, phylum
Diane Dodd raised different fruit fly populations on different food sources. She found that after
about 40 generations, the evolution of reproductive isolation was under way. The mechanism of
evolution responsible for this was
You compare homologous nucleotide sequences between several pairs of species with known
divergence times. A pair of species that diverged 1 million years ago has two nucleotide
differences, a pair that diverged 2 million years ago has four nucleotide differences, and a pair
that diverged 3 million years ago has six nucleotide differences. You have sequence data for
another pair of species where the divergence time is unknown. There are five nucleotide
differences between them. Based on your clock, when did their line of ancestry diverge?
2.5 million years ago
Miller-Urey-type experiments have shown that
complex organic molecules can be produced by physical processes from inorganic
Cave-dwelling catfish and cave-dwelling salamanders share striking similarities: both
organisms lack pigmentation and their eyes are reduced or absent. The most recent common
ancestor to these organisms had normal pigmentation and fully developed eyes. The similarities
between cave catfish and cave salamanders are an example of
analogy (convergent evolution).
Which of the following types of reproductive barriers separates a pair of moth species that could
interbreed except that the females' mating pheromones are not attractive to the males of the
Which highly reactive gas was probably absent from the Earth's primitive atmosphere?
O2 (oxygen gas)
The biological species concept is
sometimes difficult to put into practice even for present sexual organisms, and useless for
asexual organisms and fossils.
A rabbit population consists of animals that are either very dark on top or very light on top. The
color pattern is not related to sex. No rabbit shows intermediate coloration (medium darkness).
This pattern might result from
Imagine that you are studying a very large population of moths that is isolated from gene flow.
A single gene controls wing color. Half of the moths have white-spotted wings (genotype WW
or Ww) and half of the moths have plain brown wings (ww). There are no new mutations,
individuals mate randomly, and there is no natural selection on wing color. How will p, the
frequency of the dominant allele, change over time?
p will neither increase nor decrease; it will remain more or less constant under the
Which of the following represents a pair of homologous structures?
the wing of a bat and the flipper of a whale
Which of the following disciplines has found evidence for evolution based on the native
distributions (locations) of living species?
Which of the following best expresses the concept of natural selection?
differential reproductive success based on inherited characteristics
The variation in gene pools between the 30 pupfish populations occurred through an
evolutionary mechanism called
the bottleneck effect.