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| 773914951 | How does a bacterial cell protect its own DNA from restriction enzymes? A) adding methyl groups to adenines and cytosines B) using DNA ligase to seal the bacterial DNA into a closed circle C) adding histones to protect the double-stranded DNA D) forming "sticky ends" of bacterial DNA to prevent the enzyme from attaching E) reinforcing the bacterial DNA structure with covalent phosphodiester bonds | adding methyl groups to adenines and cytosines | |
| 773914952 | A gene that contains introns can be made shorter (but remain functional) for genetic engineering purposes by using A) RNA polymerase to transcribe the gene. B) a restriction enzyme to cut the gene into shorter pieces. C) reverse transcriptase to reconstruct the gene from its mRNA. D) DNA polymerase to reconstruct the gene from its polypeptide product. E) DNA ligase to put together fragments of the DNA that codes for a particular polypeptide | reverse transcriptase to reconstruct the gene from its mRNA. | |
| 773914953 | A student wishes to clone a sequence of DNA of ~200 kb. Which vector would be appropriate? A) a plasmid B) a typical bacteriophage C) a BAC D) a plant virus E) a large polypeptide | a BAC | |
| 773914954 | Which of the following is used to make complementary DNA (cDNA) from RNA? A) restriction enzymes B) gene cloning C) DNA ligase D) gel electrophoresis E) reverse transcriptase | reverse transcriptase | |
| 773914955 | DNA fragments from a gel are transferred to a nitrocellulose paper during the procedure called Southern blotting. What is the purpose of transferring the DNA from a gel to a nitrocellulose paper? A) to attach the DNA fragments to a permanent substrate B) to separate the two complementary DNA strands C) to transfer only the DNA that is of interest D) to prepare the DNA for digestion with restriction enzymes E) to separate out the PCRs | to attach the DNA fragments to a permanent substrate | |
| 773914956 | In 1997, Dolly the sheep was cloned. Which of the following processes was used? A) use of mitochondrial DNA from adult female cells of another ewe B) replication and dedifferentiation of adult stem cells from sheep bone marrow C) separation of an early stage sheep blastula into separate cells, one of which was incubated in a surrogate ewe D) fusion of an adult cell's nucleus with an enucleated sheep egg, followed by incubation in a surrogate E) isolation of stem cells from a lamb embryo and production of a zygote equivalent | fusion of an adult cell's nucleus with an enucleated sheep egg, followed by incubation in a surrogate | |
| 773914957 | Which of the following is true of embryonic stem cells but not of adult stem cells? A) They can differentiate into many cell types. B) They make up the majority of cells of the tissue from which they are derived. C) They can continue to replicate for an indefinite period. D) They can provide enormous amounts of information about the process of gene regulation. E) One aim of using them is to provide cells for repair of diseased tissue | They make up the majority of cells of the tissue from which they are derived. | |
| 773914958 | In animals, what is the difference between reproductive cloning and therapeutic cloning? A) Reproductive cloning uses totipotent cells, whereas therapeutic cloning does not. B) Reproductive cloning uses embryonic stem cells, whereas therapeutic cloning does not. C) Therapeutic cloning uses nuclei of adult cells transplanted into enucleated nonfertilized eggs. D) Therapeutic cloning supplies cells for repair of diseased or injured organs. | Therapeutic cloning supplies cells for repair of diseased or injured organs. | |
| 773914959 | The first cloned cat, called Carbon Copy, was a calico, but she looked significantly different from her female parent. Why? A) The environment, as well as genetics, affects phenotypic variation. B) Fur color genes in cats are influenced by differential acetylation patterns. C) Cloned animals have been found to have a higher frequency of transposon activation D) X inactivation in the embryo is random and produces different patterns. E) The telomeres of the parent's chromosomes were shorter than those of an embryo. | X inactivation in the embryo is random and produces different patterns. | |
| 773914960 | Which of the following is one of the technical reasons why gene therapy is problematic? A) Most cells with an engineered gene do not produce gene product. B) Most cells with engineered genes overwhelm other cells in a tissue. C) Cells with transferred genes are unlikely to replicate. D) Transferred genes may not have appropriately controlled activity. E) mRNA from transferred genes cannot be translated. | Transferred genes may not have appropriately controlled activity. | |
| 773914961 | Plants are more readily manipulated by genetic engineering than are animals because A) plant genes do not contain introns. B) more vectors are available for transferring recombinant DNA into plant cells. C) a somatic plant cell can often give rise to a complete plant. D) genes can be inserted into plant cells by microinjection. E) plant cells have larger nuclei. | a somatic plant cell can often give rise to a complete plant. | |
| 773914962 | DNA technology has many medical applications. Which of the following is not done routinely at present? A) production of hormones for treating diabetes and dwarfism B) production of microbes that can metabolize toxins C) introduction of genetically engineered genes into human gametes D) prenatal identification of genetic disease alleles E) genetic testing for carriers of harmful alleles | introduction of genetically engineered genes into human gametes | |
| 773925170 | Which of the following statements best describes theories? A) They are nearly the same things as hypotheses. B) They are supported by, and make sense of, many observations. C) They cannot be tested because the described events occurred only once. D) They are predictions of future events. | They are supported by, and make sense of, many observations. | |
| 773925171 | What was the prevailing belief prior to the time of Lyell and Darwin? A) Earth is a few thousand years old, and populations are unchanging. B) Earth is a few thousand years old, and populations gradually change. C) Earth is millions of years old, and populations rapidly change. D) Earth is millions of years old, and populations are unchanging. E) Earth is millions of years old, and populations gradually change. | Earth is a few thousand years old, and populations are unchanging. | |
| 773925172 | Which of the following is the most accurate summary of Cuvier's consideration of fossils found in the vicinity of Paris? A) extinction of species yes; evolution of new species yes B) extinction of species no; evolution of new species yes C) extinction of species yes; evolution of new species no D) extinction of species no; evolution of new species yes | extinction of species yes; evolution of new species no | |
| 773925173 | Charles Darwin was the first person to propose A) that evolution occurs. B) a mechanism for how evolution occurs. C) that Earth is older than a few thousand years. D) a mechanism for evolution that was supported by evidence. E) that population growth can outpace the growth of food resources. | a mechanism for evolution that was supported by evidence. | |
| 773925174 | Natural selection is based on all of the following except A) genetic variation exists within populations. B) the best-adapted individuals tend to leave the most offspring. C) individuals who survive longer tend to leave more offspring than those who die young. D) populations tend to produce more individuals than the environment can support. E) individuals adapt to their environments and, thereby, evolve. | individuals adapt to their environments and, thereby, evolve. | |
| 773925175 | The role that humans play in artificial selection is to A) determine who lives and who dies. B) create the genetic variants, which nature then selects. C) choose which organisms breed, and which do not. D) train organisms to breed more successfully. E) perform artificial insemination. | choose which organisms breed, and which do not | |
| 773925176 | The rise of methicillin-resistant Staphylococcus aureus (MRSA) can be considered to be an example of artificial selection because A) humans purposefully raise MRSA in large fermenters in an attempt to make the bacteria ever-more resistant. B) S. aureus is cultivated by humans to replenish the soil with nutrients. C) humans synthesize methicillin and create environments in which bacteria frequently come into contact with methicillin. D) Humans are becoming resistant to bacteria by taking methicillin. | humans synthesize methicillin and create environments in which bacteria frequently come into contact with methicillin. | |
| 773925177 | Over evolutionary 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? A) Natural selection cannot account for losses, only for innovations. B) Natural selection accounts for these losses by the principle of use and disuse. C) Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits. D) The ancestors of these organisms experienced harmful mutations that forced them to find new habitats that these species had not previously used. | Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits. | |
| 773925178 | Which of the following pieces of evidence most strongly supports the common origin of all life on Earth? A) All organisms require energy. B) All organisms use essentially the same genetic code. C) All organisms reproduce. D) All organisms show heritable variation. E) All organisms have undergone evolution. | All organisms use essentially the same genetic code. | |
| 773925179 | What is true of pseudogenes? A) They are composed of RNA, rather than DNA. B) They are the same things as introns. C) They are unrelated genes that code for the same gene product. D) They are vestigial genes. | They are vestigial genes. | |
| 773925180 | It has been observed that organisms on islands are different from, but closely related to, similar forms found on the nearest continent. This is taken as evidence that A) island forms and mainland forms descended from common ancestors. B) common environments are inhabited by the same organisms. C) the islands were originally part of the continent. D) the island forms and mainland forms are converging. E) island forms and mainland forms have identical gene pools. | island forms and mainland forms descended from common ancestors. | |
| 773925181 | 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? A) Humans and bats evolved by natural selection, and whales evolved by Lamarckian mechanisms. B) Forelimb evolution was adaptive in people and bats, but not in whales. C) Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy. D) Genes mutate faster in whales than in humans or bats. E) Whales are not properly classified as mammals. | Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy. |
