Chapter 22 Mastering Bio

Which term describes a trait that increases an individual's ability to survive in a particular environment?

Adaptation- trait that increases an individual's ability to survive in a particular environment.

Which of the following observations led to Darwin's major inferences?

Members of a population vary in their heritable traits. & Although organisms can produce huge numbers of offspring, many of these offspring do not survive.

Parasitic species tend to have simple morphologies. Which of the following statements best explains this observation?

Simple morphologies convey some advantage in most parasites.

From his observations of organisms in the Galapagos islands, Darwin reasoned that _____.

organisms had adapted to new environments, giving rise to new species

Identify the pair of homologous structures.

Maple leaf and oak leaf. The common ancestor of maple and oak trees had leaves, and maple and oak leaves have evolved from that ancestral structure. Homologous structures may be quite similar in structure and function (such as maple and oak leaves) or quite different (such as maple leaves and cactus spines).

A farmer wishes to develop a strain of high-yield corn that is also resistant to drought. He has the following individuals from the current year's crop: Individual A—Yield: 179 bushels/acre; drought resistance: high Individual B—Yield: 220 bushels/acre; drought resistance: low Individual C—Yield: 185 bushels/acre; drought resistance: medium Individual D—Yield: 140 bushels/acre; drought resistance: high Individual E—Yield: 200 bushels/acre; drought resistance: medium Which of the following crosses would produce the highest corn yield with the highest resistance to drought?

A and E This cross would result in an average corn yield of 189.5 bushels/acre and have a medium-high drought resistance, which is the best you can get for both traits.

Which of the following organisms could be produced by artificial selection?

A cow that produces a large quantity of milk.

The following question refer to the figure below, which shows an outcrop of sedimentary rock whose strata are labeled A-D. If x indicates the location of fossils of two closely related species, then fossils of their most-recent common ancestor are most likely to occur in which stratum?

C

During a study session about evolution, one of your fellow students remarks, "The giraffe stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a result." Which statement is most likely to be helpful in correcting this student's misconception?

Characteristics acquired during an organism's life are generally not passed on through genes

Darwin and Wallace's theory of evolution by natural selection was revolutionary because it

Dismissed the idea that species are constant and emphasized the importance of variation and change in populations

Which term describes the ability of a trait to be passed on to offspring?

Heritability- the ability of a trait to be passed on to offspring.

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, which develop from similar embryonic tissues. These structural similarities are an example of _____.

Homology

Starting from the wild mustard Brassica oleracea, breeders have created the strains known as Brussels sprouts, broccoli, kale, and cabbage. Therefore, which of the following statements is correct?

In this wild mustard, there is enough heritable variation to permit these different varieties.

What must be true of any organ described as vestigial?

It must be homologous to some feature in an ancestor.

Which of the following statements about natural selection is true?

Natural selection favors individuals that reproduce more than others.

The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data?

Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy.

In 1959, doctors began using the powerful antibiotic methicillin to treat infections of Staphylococcus aureus, but within two years, methicillin-resistant strains of S. aureus (MRSA) appeared. How did the resistant strains of S. aureus emerge?

Staphylococcus aureus bacteria that were able to synthesize cell walls using a protein that was not affected by methicillin survived the methicillin treatments and reproduced at higher rates than did other individuals. Over time, these resistant individuals became increasingly common.

Varieties of Staphylococcus aureus that are resistant to the drug methicillin _____.

already existed in the population before methicillin was developed. & were strongly selected for as methicillin became widely used to treat bacterial infections

Which of the following is(are) homologous to the bones in this image?

The digits of a cat are homologous to those of these whale bones.

Catastrophism was Cuvier's attempt to explain the existence of

The fossil record

A farmer uses triazine herbicide to control pigweed in his field. For the first few years, the triazine works well and almost all the pigweed dies; but after several years, the farmer sees more and more pigweed. Which of these explanations best explains what happened?

Triazine-resistant weeds were more likely to survive and reproduce.

Over long periods of time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses?

Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits.

An adaption is _____

a trait that gives an organism a reproductive advantage in the current environment.

A population of organisms will not evolve if _____.

all individual variation is due only to environmental factors

The cow Bos primigenius (which is bred for meat and milk) has a smaller brain and larger eyes than closely related wild species of ungulates. These traits most likely arose by _____.

artificial selection, because changes in these traits co-occurred with human selection for high milk output and high muscle content

The role that humans play in artificial selection is to _____.

choose which organisms reproduce

The wing of a bat is homologous to the _____ of a whale.

flipper

Which of the following must exist in a population before natural selection can act upon that population?

genetic variation among individuals

DNA sequences in many human genes are very similar to the sequences of corresponding genes in chimpanzees. The most likely explanation for this result is that

humans and chimpanzees share a relatively recent common ancestor.

The greatest number of endemic species is expected in environments that are _____.

isolated and show little ecological diversity

Charles Darwin

proposed natural selection as the mechanism of evolution