Evoultion – Flashcard
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Populations change naturally over time. Which mechanism is a method of artifical selection rather than natural selection?
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Selective breeding
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The graph above was made by a biologist working in the Galapagos islands. The biologist examined the stomach contents of the ground finch, the leaf finch, and the cactus finch, to determine what foods they usually ate. The graph shows the average number of seeds of the 4 most common plant species found in the stomach of each type of bird. Based on the graph, which statement is correct about the relationship between the ground finch and the cactus finch?
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Ground finches and cactus finches mostly occupy different feeding niches
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The sequence of ________________ in a DNA molecule determines the protein that will be produced.
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nucleotides
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African cichlids are a group of closely related fish species. There are at least 500 known species living in three small lakes. Over time, specialized teeth and body colorations have evolved for each species in response to mutations and competition for food and mates. This change over time is an example of
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Adaptive radiation.
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Which pair of organisms show convergent evolution?
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Tasmanian devils and wolverines are both thick-bodied predators with crushing teeth and both eat carrion, but they are not at all related.
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The diagram shows the leg bones of a (L -> R): Orangutan, dog, pig, cow, tapir, and horse. Most of the animals have the same bones, although some are shaped differently and placed in different positions. What does this suggest about mammals?
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That they shared a common ancestor
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Green and brown algae share many common features. Both have pigments for trapping sunlight and use photosynthesis for energy. Both store their food as sugars. Both have cell walls and plant-like bodies. However, their DNA suggests that they are not even remotely related to one another. Green algae and brown algae show __________________ evolution, since they look similar, but are not close relatives
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Convergent
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Darwin discovered twenty different species of finches in the Galapagos islands. He hypothesized that as new islands arose, finches colonized the islands and rapidly changed into new species, depending on what food was available on each new island. The rapid formation of many new species, as in this case, is called
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Adaptive radiation
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Which word pair makes the following statement true? The process of ___________________leads to the formation of new species by ___________________.
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natural selection, evolution.
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The wing of a bird and the leg of a horse are very different looking structures. Although they look different, bird wings and horse legs are very similar in the arrangement of the bones that make up the limb. Which term is used by scientists to describe structures that look different on the outside but are actually similar in construction and develop from the same embryonic tissues?
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homologous structures.
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A change in a sequence of DNA bases in a bacterial cell has resulted in a mutation. This mutation has increased the ability of the bacteria to break down and digest organic molecules in the environment. Bacteria with this mutation are better able to find and utilize food sources. According to the theory of natural selection, what is MOST likely to occur in future generations of this bacteria?
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The relative frequency of the mutation will increase as time passes.
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Suppose orange beetles and green beetles live in the same environment. Green beetles are harder to see on leaves, so birds eat primarily orange beetles. According to the theory of natural selection, in the future orange beetles will
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decrease in population until they possibly become extinct.. Over time, there will be only green beetles as the birds eat the more visible, orange beetles.
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This adaptation which allows for natural selection is called
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mimcry
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Approximately 2 million years ago the genus Australopithecus gave rise to a new genus, Homo. Today, we retain the genus as Homo sapiens. What important fossil evidence MOST likely helped scientists change the classification of those early human ancestors?
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teeth and skull size.
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The above image shows four different finches that Charles Darwin found while on the Galapagos Islands. This information led Darwin to develop the idea that organisms change, or evolve, over time. Which of these would best describe what Darwin saw as the MAJOR difference(s) between these finches?
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both where they lived and what they ate were different.
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Biotechnology has helped produce crops that are resistant to certain pests, crops that produce high yields, and more nitrogen-efficient crops. What is a negative impact that bioengineered plants may have on the environment?
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Beneficial insects may be adversely affected.
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Darwin observed how farmers and breeders produced many kinds of farm animals and plants. These plants and animals had traits that were desired by the farmers and breeders. He also noticed how the study of similar body structures and vestigial organs could add to the evidence of evolution. After performing several breeding experiments, he came to certain conclusions and formulated some theories. His theory of evolution and natural selection is the most accepted one. What is the reason behind the acceptance of Darwin's theory?
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It is supported by practical evidence and examples
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DNA and its structure was not isolated and understood until the mid 1900s. It serves as
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the mechanism by which the "strong principle of inheritance" operates.
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Speckled and striped beans (mice) had the best survival rates. Why?
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Coloration was a form of camouflage.
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Scientists believe the first giraffes on Earth had shorter legs and a shorter neck than giraffes today. What can you conclude about these first giraffes?
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they had food sources that were low to the ground.
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When an existing population of organisms gives rise to two or more new species, the new species cannot effectively breed with one another. Which term is used to describe this phenomenon?
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reproductive isolation.
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What did Charles Darwin mean when he stated that some organisms were 'more fit' than other organisms?
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more likely to reproduce
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Evidence for evolution includes the presence of _______________________, which are similar structures shared by different species
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Homologous structures
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The genetic information in human and chimpanzee DNA shows a high degree of similarity, as humans share about 96% of their DNA code with chimpanzees. What is an explanation for this similarity?
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They evolved from a common ancestor.
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Green and brown algae share many common features. Both have pigments for trapping sunlight and use photosynthesis for energy. Both store their food as sugars. Both have cell walls and plant-like bodies. However, their DNA suggests that they are not even remotely related to one another. Green algae and brown algae show __________________ evolution, since they look similar, but are not close relatives.
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Convergent.
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Which word pair makes the following statement true? The process of ___________________leads to the formation of new species by ___________________.
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natural selection, evolution.
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A change in a sequence of DNA bases in a bacterial cell has resulted in a mutation. This mutation has increased the ability of the bacteria to break down and digest organic molecules in the environment. Bacteria with this mutation are better able to find and utilize food sources. According to the theory of natural selection, what is MOST likely to occur in future generations of this bacteria
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The relative frequency of the mutation will increase as time passes.
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How would you expect the iguanas to look many years after the island flooded and food became harder to find?
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There would be more iguanas with webbed feet and flat tails.
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What can you learn from a set of embryo drawings of vertebrates of different phyla?
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the embryo drawings of vertebrates help to learn about the phylogenetic relationships between species.
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A review of the cladogram shows a common ancestor for these four types of vertebrates. Which statement BEST explains the genetics represented by the cladogram?
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Lizards and snakes are more genetically alike than lizards and birds.
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In a typical cell membrane, phospholipids arrange themselves to form a
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Bilayer
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Many of the proteins produced by humans have identical or nearly identical counterparts in chimpanzees. For example, the hemoglobin in your blood is about 99% similar to chimp hemoglobin. This suggests that humans and chimps share a common ancestor, from which both species evolved via ____________.
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divergence
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Scientists believe that land plants, such as the examples seen here, evolved from single-celled green algae. Single-celled algae first evolved a colonial form, as noted in Volvox, and eventually developed organs for reproduction as well as food and water conduction. One key process in this evolution was
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cell differentiation
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The dots represent a bacterial infection. Sal was very sick with this bacterial infection. The infection was treated with antibiotics. Sal seemed to get well, but in a few weeks, she was sick again. How can this be explained using natural selection?
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The stronger, resistant bacteria to survive the antibiotics and reproduce.
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In order for natural selection to occur, Charles Darwin stated we must begin with a population of organisms that has genetic
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variation.
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The pygmy hippo, shown in the photograph, typically weighs no more than 500 pounds and is about the size of a large pig. The much larger river hippopotamus usually weighs between 3,000 and 6,000 pounds. There are no living species of hippos that are medium-sized. Which term is used to describe evolutionary selection which results in greater numbers of individuals at the extremes of the distribution and few at the center of the distribution?
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Disruptive
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The diagram shows a type of extinct species, pterosaur, a bat, and a type of bird, a cormorant. All three organisms have wings that look and work alike, but were not evolved from a common ancestor. Which term is used to descibe body structures that look alike and serve a similar function but are not descended from a common ancestor?
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Analogous structures
