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29 terms

Biology pt 3

STUDY
PLAY
Mutations by themselves are rarely the cause of evolution in populations of plants and animals because:
?
Large antlers in male elk, which are used for battles between males, are a good example of
Intrasexual selection
Genetic differences between populations tend to be reduced by
Gene flow
Mate-attracting features such as the bright plumage of a male peacock result from
Intersexual selection
A change in the relative frequencies of alleles in the gene pool of a population is called
microevolution
What is a mutation?
A random change in an organism's DNA
Certain whale species were hunted to near extinction. With a moratorium on hunting them, their population sizes have expanded. Which of the following is true?
The populations may still be endangered because they may have little remaining genetic variation
What is the result of natural selection?
a change in the gene pool of a population due to differential reproductive success
Which of the following provides evidence that vertebrates evolved from a common ancestor?
All of the choices are correct: similarities in protein structure, common development of pharyngeal pouches, homologous structures, the presence of similar genes
Which one of the following is false? Natural selection
Results from an organism's needs
Which one of the following is false?
All variation in a population is heritable
Natural selection is often described as "survival of the fittest" The best measure of an organism's fitness is
How many offspring it produces
Which of the following promote(s) genetic variation in a population?
All of the choices promote genetic variation in a population: balancing selection, heterozygote advantage, frequency-dependent selection
Analogous structures found in two species are structures that have
Similar overall shape due to common function
Which one of the following was not a main idea that Darwin advanced in his works?
New species can form by inheritance of acquired characteristics
The term macroevolution refers to which one of the following
Grand scale of evolution over many geological time
The unifying theme of biology is
Evolution
Tay-Sachs is inherited as an autosomal recessive allele. Homozygous individuals die within the first few years of life. However, there is some evidence that heterozygous individuals are more resistant to tuberculosis. Which of the following statements is true?
This situation is an example of heterozygote advantage
Which one of the following represents two structures that are homologous?
The wing of a bat and the flipper of a whale
Long-legged cheetahs are well adapted to catching prey. The ancestor of the cheetah is believed to have had relatively short legs. According to Darwinian views, the evolution of long-legged cheetahs is best explained by
Directional selection
A plant breeder has been trying to develop a strain of snap dragons with blue flowers from a population of snapdragons some of which have white flowers and some of which have blue flowers. He finds that no matter how careful he is to only select blue flowered snap dragons, when he plants them out side roughly 10% of the snapdragons have white flower and some plants have both blue and white flowers on the same plant. The most likely explanation is:
Selection can only act on heritable variation and the white flower is due to environment
Mutations by themselves are rarely the cause of evolution in populations of plants and animals because:
All of the above
Which of the following assumptions was not part of Darwin's theory of natural selection?
Traits are inherited as discrete particles
Fitness increases when an organism
passes on a greater proportion of its genes to the next generation
The disease phenylketonuria (PKU. is caused by a recessive allele, and one child in 10,000 is born with the disease. Let q represent the frequency of the PKU allele. What is the value of q2? (Fetuses with PKU are no likelier than other fetuses to die before birth..
0.0001
A population of 1,000 birds exists on a small Pacific island. Some of the birds are yellow, a characteristic determined by a recessive allele. The others are green, a characteristic determined by a dominant allele. A hurricane on the island kills most of the birds from this population. Only ten remain, and those birds all have yellow feathers. Which of the following statements is true?
The hurricane has caused a population bottleneck
What term is used to refer to structures that have a similar origin or ancestry even though they may be very different in appearance?
Homologous
In a cell in which 2n = 6, the independent assortment of chromosomes during meiosis can by itself give rise to __________ genetically different gametes
eight
A population is
the smallest unit that can evolve