bio chapter 16 – Flashcards

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At one point, you were just an undifferentiated, single cell. You are now made of many cells; some of these cells function as liver cells, some as muscle cells, some as red blood cells, while others play different roles. What name is given to the process that is responsible for this?
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cellular differentiation
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The process by which genotype becomes expressed as phenotype is ______.
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gene expression
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In bacteria, what name is given to a cluster of genes with related functions, along with their control sequences?
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operon
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Bacterial RNA polymerase binds to the ______.
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promoter
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In prokaryotes, the production of a single RNA transcript for a group of related genes is under the control of the ______.
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operon
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) In an operon, the ______ acts as an on/off switch.
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operator
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Which of the following turns off transcription by binding to the operator?
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repressors
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Repressors act by blocking the binding of _____ to the operator.
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RNA polymerase
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What would you assume if you found RNA transcripts of lactose-utilizing genes within E. coli?
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the presence of lactose
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While examining a human cell that functions normally, you determine that it has 45 functional chromosomes and one chromosome that is almost completely inactive. You immediately decide that it is very likely that this cell ______.
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came from a normal human female
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What is the first level of control of eukaryotic gene transcription?
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DNA packing and unpacking
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Male tortoiseshell cats ______.
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) are likely to be exceedingly rare and very likely to be sterile since normal male cats are XY
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Which of these plays a role in the regulation of transcription in both prokaryotic and eukaryotic cells?
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attachment of RNA polymerase to the promoter
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In eukaryotic cells, repressor proteins inhibit transcription by binding to ______.
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silencers
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Introns are ______.
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noncoding DNA sequences
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Which of these is a type of post-transcriptional regulation of gene expression?
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alteration of proteins
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How can a single RNA transcript be translated into different polypeptides?
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There is more than one way to splice an RNA transcript.
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Cells communicate with one another via ______.
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signal transduction pathways
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Which of these techniques could tell you how gene expression differs between individuals with and without cystic fibrosis?
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DNA microarray
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How is it that the cells in different body tissues are able to perform different functions?
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The cells exhibit different patterns of gene expression
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To make a clonea genetically identical organismfrom a mammalian cell, the cell must ______.
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be dedifferentiated
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what is a difference between embryonic and adult stem cells?
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Embryonic stem cells are undifferentiated; adult stem cells are partially differentiated.
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What name is given to a gene that causes cancer?
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oncogene
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Many proto-oncogenes regulate ______.
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cell division
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Inheritance of certain genes increases the risk of getting certain cancers; thus, it can be said that ______.
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predisposition to these cancers is inherited
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Data suggest that the normal version of BRCA1 functions as a(n) ______.
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tumor-suppressor gene
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One of the most potent environmental carcinogens is ______.
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UV radiation
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More people die of ______ cancer than of any other cancer.
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lung
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Which of these is most likely to cause the development of a six-legged frog?
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mutation of homeotic genes
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Developmental similarities among very different animals, such as fruit flies and mice, can be attributed to ______.
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shared homeoboxes
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Homeoboxes ______.
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are evidence of the common ancestry of eukaryotic organisms
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Which of the following is the best definition for recombinant DNA?
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DNA that carries genes from two different sources
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Which of these is a genetically modified organism?
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an organism carrying a gene that was acquired by artificial means
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Which of the following best defines the term transgenic animal?
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an animal containing a gene from a another species
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The world's first genetically engineered pharmaceutical product was ______.
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humulin
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A vaccine works by ______.
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stimulating the immune system to develop lasting defenses
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Transgenic animals are currently used ______.
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to produce potentially useful proteins
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Which of these can act as a vector to introduce new genes into a cell?
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plasmids
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Of these steps, which occurs first in the production of a recombinant plasmid?
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isolation of a plasmid from a bacterium
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Of these steps, which one occurs earliest in the process of producing recombinant DNA?
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The same restriction enzyme is used to isolate the gene of interest and to cut the plasmid DNA.
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When plasmids are used to produce a desired protein, the ______.
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desired gene is inserted into the plasmid and the plasmid is taken up by the bacterium
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The process of making multiple copies of a gene by inserting it into a host genome and culturing the host is an example of ______.
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gene cloning
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A collection of cloned recombinant plasmids that includes fragments from the entire genome of a cell is called a ______.
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genomic library
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Nucleic acid probes are used to ______.
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find a specific nucleotide sequence
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Restriction enzymes are obtained from ______.
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bacteria
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"Sticky ends" are produced as a result of the action of ______.
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a restriction enzyme
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"Sticky ends" are ______.
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single-stranded ends of fragments of double-stranded DNA
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A DNA fragment with a sticky end that reads -ATTCG will bind with another DNA fragment with a sticky end that reads ______.
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TAAGC-
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Which enzyme is used to bind DNA fragments together?
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DNA ligase
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Of the following, which is the last step in the production of a recombinant DNA plasmid?
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using DNA ligase to join DNA fragments
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You are attempting to link an individual to a crime. The only evidence you have is a tiny drop of blood. How can you use this drop of blood to make the association?
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You can use PCR to increase the amount of DNA available for restriction fragment analysis.
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What name is given to a region of DNA that varies from person to person?
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genetic marker
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Cutting DNA with a particular restriction enzyme produces DNA fragments that can be separated by ______.
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gel electrophoresis
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To make restriction fragments, a DNA sample is treated with ______.
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restriction enzymes
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Gel electrophoresis separates DNA fragments on the basis of differences in their ______.
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length
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The scientific field that studies whole genomes is called ______.
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genomics
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The human genome contains approximately ______ genes.
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21,000
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Approximately what percentage of the human genome consists of noncoding DNA?
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98%
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In the future, scientists hope to be able to compare whole genomes of individuals, a new field called ______.
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Comparative genomics
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Which of these statements can be logically inferred from the amount of DNA shared by chimpanzees and humans?
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Humans and chimpanzees share a relatively recent common ancestor
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To find the nucleotide sequence of human chromosomes, chromosomes had to be digested into small fragments and then ______.
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cloned and sequenced
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What technique is most commonly used to sequence entire genomes?
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the whole-genome shotgun approach
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The study of the full protein sets that genomes encode is _____.
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proteomics
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Genetically modifying human ______ cells may directly affect future generations.
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gametic
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The possibility that Mongolian ruler Genghis Khan spread an unusual chromosome to nearly 16 million men living today resulted from studies of _____.
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the Y chromosome
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The first basic idea of evolutionary adaptation can be traced back to _____.
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Lamarck
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During his trip on the Beagle, Darwin found that ______.
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plants and animals living on a continent seemed more closely related to each other than to plants and animals living in similar regions on other continents
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While on the Beagle, Darwin was influenced by a book by Charles Lyell that suggested that Earth was ______ and sculpted by geologic processes that ______ today.
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old . . . continue
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What did Darwin find in South America that suggested that the Andes mountains had been gradually lifted up over millions of years?
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sea snail fossils high up in the Andes mountains
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Your family is taking a long driving vacation across the midwestern and western United States. As you travel, you notice that the flowers, birds, and trees of the Midwest and the Rocky Mountains are very different. As you ponder why, you remember that such differences in the distribution of species are part of the field of ______.
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biogeography
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Homology is evidence of ______.
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common ancestry
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Which of the following are homologous?
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the forelimb of a dog and the forelimb of a cat
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) The similarity of the embryos of fish, frogs, birds, and humans is evidence of ______.
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common ancestry
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Which of the following is not a requirement of natural selection?
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catastrophic events
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Which one of the following statements is true?
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Natural selection works on variation already present in a population.
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Research on flat-tailed horned lizards demonstrated that natural selection favored lizards that ______.
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had the longest horns on the rear of the skull
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The modern synthesis was a fusion of ______.
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biogeography and comparative embryology
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Which of the following is a population?
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all organisms living in your house
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The smallest unit of evolution is the ______.
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population
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Which of the following is likely to be the result of polygenic inheritance?
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human height
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Which one of the following can create new alleles?
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mutation
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All of the alleles of all of the genes within a population make up that population's ______.
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gene pool
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If the frequency of one allele in a population is 0.7, what is the frequency of the alternate allele?
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0.30
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In the Hardy-Weinberg formula, what does p2 represent?
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frequency of the homozygous dominants
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In the Hardy-Weinberg formula, what does 2pq represent?
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frequency of heterozygotes
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The presence of freckles is due to a dominant allele. Four percent of the individuals in a particular population lack freckles. Use the Hardy-Weinberg formula to calculate the percentage of individuals in this population who are homozygous dominant for freckles.
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64%
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The original source of genetic variation that serves as the raw material for natural selection is ______.
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mutation
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Which of the following is a characteristic of a population at Hardy-Weinberg equilibrium?
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The population is not evolving
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Genetic drift is the result of ______.
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chance
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Which one of the following will prevent significant genetic drift?
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The population size is large.
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After surviving a bottleneck, a population recovers to the point where it consists of as many individuals as it did prior to the bottleneck. Which of the following statements is most likely to apply to this population?
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The postbottleneck population exhibits less genetic variation than the prebottleneck population.
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The founder effect differs from a population bottleneck in that the founder effect ______.
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involves the isolation of a small colony of individuals from a larger population
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Which of the following is the most likely explanation for a particular human population with a higher incidence of polydactyly (extra fingers/toes) than the human population as a whole?
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founder effect
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Gene flow is accomplished by ______.
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migration
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What does Darwinian fitness measure?
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REPRODUCTIVE SUCCESS
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Which of the following is an example of directional selection?
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There is an increase in antibiotic-resistant strains of bacteria.
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Which of the following is an example of disruptive selection?
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Garter snakes with different coloration patterns behave differently when threatened.
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Which of the following is most likely to decrease genetic variation?
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stabilizing selection
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Which of the following is an example of stabilizing selection?
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THe birth weight at which newborn humans are most likely to survive and the average weight of newborn humans are about the same.
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Which of the following is an example of sexual selection?
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Peahens choose to mate with peacocks that have the most beautiful tails.
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Eukaryotes arose about ______ years after the first prokaryotes.
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1.5 billion
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Large amounts of oxygen gas appeared in Earth's atmosphere about ______ years ago.
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2.7 billion
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Animal life underwent its greatest diversification during the ______, which began about ______ million years ago.
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Cambrian . . . 540
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Which kingdom(s) was(were) the first to colonize land?
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Plantae and Fungi
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Land was first colonized about ______ years ago.
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500 million
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The idea that life regularly arises from nonliving matter is referred to as ______.
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spontaneous generation
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The absence of ______ in the primitive atmosphere was essential to the origin of life on Earth.
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O2
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What was the first stage of the process that led to the abiotic origin of life?
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abiotic synthesis of monomers, such as amino acids and nucleotides
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Whose experiments demonstrated that, given the conditions on the primitive Earth, biological monomers could arise spontaneously?
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Miller and Urey
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Under what abiotic conditions can monomers spontaneously form polymers?
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when water evaporates from a hot surface
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Why is RNA thought to have been the first genetic material?
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RNA is capable of self-replication; DNA is not.
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RNAs that can act as enzymes are called ______.
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ribozymes
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Variation among pre-cells was due to ______.
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mutation
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Which prokaryotic group is most closely related to eukaryotes?
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domain Archaea
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The prokaryotic group that tends to inhabit extreme environments belongs to the ______.
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domain Archaea
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Which of the following are primarily responsible for an unfortunate side effect of eating beans?
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dinoflagellates
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Spherical bacteria that occur in clusters are ______.
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staphylococci
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Which of the following would likely be the most difficult to kill were you to can your own food?
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endospores
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Prokaryotes reproduce by means of ______.
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binary fission
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Under ideal conditions, prokaryotes are capable of reproducing at a(n) ______ rate.
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exponential
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