In recombinant DNA methods, the term vector can refer to

In recombinant DNA methods, the term vector can refer to 

A) the enzyme that cuts DNA into restriction fragments.
B) the sticky end of a DNA fragment.
C) a RFLP marker.
D) a plasmid used to transfer DNA into a living cell.
E) a DNA probe used to identify a particular gene.

Answer: D

Which of the following sequences in double-stranded DNA is most likely to be recognized as a cutting site for a restriction enzyme?

Which of the following sequences in double-stranded DNA is most likely to be recognized as a cutting site for a restriction enzyme? 

A)
AAGG
TTCC
B)
AGTC
TCAG
C)
GGCC
CCGG
D)
ACCA
TGGT
E)
AAAA
TTTT

Answer: C

DNA technology has many medical applications. Which of the following is not done routinely at present?

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 viral proteins for vaccines
C) introduction of genetically engineered genes into human gametes
D) prenatal identification of genetic disease genes
E) genetic testing for carriers of harmful alleles

Answer: C

Expression of a cloned eukaryotic gene in a bacterial cell involves many challenges. The use of mRNA and reverse transcriptase is part of a strategy to solve the problem of

Expression of a cloned eukaryotic gene in a bacterial cell involves many challenges. The use of mRNA and reverse transcriptase is part of a strategy to solve the problem of 

A) post-transcriptional processing.
B) electroporation.
C) post-translational processing.
D) nucleic acid hybridization.
E) restriction fragment ligation.

Answer: A

A paleontologist has recovered a bit of tissue from the 400-year-old preserved skin of an extinct dodo (a bird). The researcher would like to compare a specific region of the DNA from the sample with DNA from living birds. Which of the following would be most useful for increasing the amount of dodo DNA available for testing?

A paleontologist has recovered a bit of tissue from the 400-year-old preserved skin of an extinct dodo (a bird). The researcher would like to compare a specific region of the DNA from the sample with DNA from living birds. Which of the following would be most useful for increasing the amount of dodo DNA available for testing? 

A) RFLP analysis
B) polymerase chain reaction (PCR)
C) electroporation
D) gel electrophoresis
E) Southern blotting

Answer: B

Plants are more readily manipulated by genetic engineering than are animals because

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.

Answer: C

Which of the following would not be true of cDNA produced using human brain tissue as the starting material?

Which of the following would not be true of cDNA produced using human brain tissue as the starting material? 

A) It could be amplified by the polymerase chain reaction.
B) It could be used to create a complete genomic library.
C) It is produced from mRNA using reverse transcriptase.
D) It could be used as a probe to detect genes expressed in the brain.
E) It lacks the introns of the human genes.

Answer: B

Which of the following tools of recombinant DNA technology is incorrectly paired with its use?

Which of the following tools of recombinant DNA technology is incorrectly paired with its use? 

A) restriction enzyme-production of RFLPs
B) DNA ligase-enzyme that cuts DNA, creating the sticky ends of restriction fragments
C) DNA polymerase-used in a polymerase chain reaction to amplify sections of DNA
D) reverse transcriptase-production of cDNA from mRNA
E) electrophoresis-separation of DNA fragments

Answer: B

As genetic technology makes testing for a wide variety of genotypes possible, which of the following is likely to be an increasingly troublesome issue?

As genetic technology makes testing for a wide variety of genotypes possible, which of the following is likely to be an increasingly troublesome issue? 

A) use of genotype information to provide positive identification of criminals
B) using technology to identify genes that cause criminal behaviors
C) the need to legislate for the protection of the privacy of genetic information
D) discrimination against certain racial groups because of major genetic differences
E) alteration of human phenotypes to prevent early disease

Answer: C

One possible use of transgenic plants is in the production of human proteins, such as vaccines. Which of the following is a possible hindrance that must be overcome?

One possible use of transgenic plants is in the production of human proteins, such as vaccines. Which of the following is a possible hindrance that must be overcome? 

A) prevention of transmission of plant allergens to the vaccine recipients
B) prevention of vaccine-containing plants being consumed by insects
C) use of plant cells to translate non-plant derived mRNA
D) inability of the human digestive system to accept plant-derived protein
E) the need to cook all such plants before consuming them

Answer: A

Which of the following is one of the technical reasons why gene therapy is problematic?

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.

Answer: D

One successful form of gene therapy has involved delivery of an allele for the enzyme adenosine deaminase (ADA) to bone marrow cells of a child with SCID, and delivery of these engineered cells back to the bone marrow of the affected child. What is one major reason for the success of this procedure as opposed to many other efforts at gene therapy?

One successful form of gene therapy has involved delivery of an allele for the enzyme adenosine deaminase (ADA) to bone marrow cells of a child with SCID, and delivery of these engineered cells back to the bone marrow of the affected child. What is one major reason for the success of this procedure as opposed to many other efforts at gene therapy? 

A) The engineered bone marrow cells from this patient can be used for any other SCID patient.
B) The ADA introduced allele causes all other ADA-negative cells to die.
C) The engineered cells, when reintroduced into the patient, find their way back to the bone marrow.
D) No vector is required to introduce the allele into ADA-negative cells
E) The immune system fails to recognize cells with the variant gene

Answer: C

Scientists developed a set of guidelines to address the safety of DNA technology. Which of the following is one of the adopted safety measures?

Scientists developed a set of guidelines to address the safety of DNA technology. Which of the following is one of the adopted safety measures? 

A) Microorganisms used in recombinant DNA experiments are genetically crippled to ensure that they cannot survive outside of the laboratory.
B) Genetically modified organisms are not allowed to be part of our food supply.
C) Transgenic plants are engineered so that the plant genes cannot hybridize.
D) Experiments involving HIV or other potentially dangerous viruses have been banned.
E) Recombinant plasmids cannot be replicated.

Answer: A

Genetically engineered plants

Genetically engineered plants 

A) are more difficult to engineer than animals.
B) include a transgenic rice plant that can help prevent vitamin A deficiency.
C) are being rapidly developed, but traditional plant breeding programs are still the only method used to develop new plants.
D) are able to fix nitrogen themselves.
E) are banned throughout the world.

Answer: B

Genetic engineering is being used by the pharmaceutical industry. Which of the following is not currently one of the uses?

Genetic engineering is being used by the pharmaceutical industry. Which of the following is not currently one of the uses? 

A) production of human insulin
B) production of human growth hormone
C) production of tissue plasminogen activator
D) genetic modification of plants to produce vaccines
E) creation of products that will remove poisons from the human body

Answer: E

Gene therapy

Gene therapy 

A) has proven to be beneficial to HIV patients.
B) involves replacement of a defective allele in sex cells.
C) cannot be used to correct genetic disorders.
D) had apparent success in treating disorders involving bone marrow cells.
E) is a widely accepted procedure.

Answer: D

Which of the following are probably siblings?

Which of the following are probably siblings? 

A) A and B
B) A and C
C) A and D
D) C and D
E) B and D

Answer: D

Which of the following statements is most likely true?

Which of the following statements is most likely true? 

A) D is the child of A and C.
B) D is the child of A and B.
C) D is the child of B and C.
D) A is the child of C and D.
E) B is the child of A and C.

Answer: B

Which of the following statements is consistent with the results?

Which of the following statements is consistent with the results? 

A) B is the child of A and C.
B) C is the child of A and B.
C) D is the child of B and C.
D) A is the child of B and C.
E) A is the child of C and D.

Answer: B

A researcher is using adult stem cells and comparing them to other adult cells from the same tissue. Which of the following is a likely finding?

A researcher is using adult stem cells and comparing them to other adult cells from the same tissue. Which of the following is a likely finding? 

A) The cells from the two sources exhibit different patterns of DNA methylation.
B) Adult stem cells have more DNA nucleotides than their counterparts.
C) The two kinds of cells have virtually identical gene expression patterns in microarrays.
D) The non-stem cells have fewer repressed genes.
E) The non-stem cells have lost the promoters for more genes.

Answer: A

Which of the following is true of embryonic stem cells but not of adult stem cells?

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.

Answer: B

Reproductive cloning of human embryos is generally considered unethical. However, on the subject of therapeutic cloning there is a wider divergence of opinion. Which of the following is a likely explanation?

Reproductive cloning of human embryos is generally considered unethical. However, on the subject of therapeutic cloning there is a wider divergence of opinion. Which of the following is a likely explanation? 

A) Use of adult stem cells is likely to produce more cell types than use of embryonic stem cells.
B) Cloning to produce embryonic stem cells may lead to great medical benefits for many.
C) Cloning to produce stem cells relies on a different initial procedure than reproductive cloning.
D) A clone that lives until the blastocyst stage does not yet have human DNA.
E) No embryos would be destroyed in the process of therapeutic cloning

Answer: B

Which of the following problems with animal cloning might result in premature death of the clones?

Which of the following problems with animal cloning might result in premature death of the clones? 

A) use of pluripotent instead of totipotent stem cells
B) use of nuclear DNA as well as mtDNA
C) abnormal regulation due to variant methylation
D) the indefinite replication of totipotent stem cells
E) abnormal immune function due to bone marrow dysfunction

Answer: C

In 1997, Dolly the sheep was cloned. Which of the following processes was used?

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

Answer: D

Which of the following is most closely identical to the formation of twins?

Which of the following is most closely identical to the formation of twins? 

A) cell cloning
B) therapeutic cloning
C) use of adult stem cells
D) embryo transfer
E) organismal cloning

Answer: E

Which of the following techniques used to analyze gene function depends on the specificity of DNA base complementarity?

Which of the following techniques used to analyze gene function depends on the specificity of DNA base complementarity? 

A) Northern blotting
B) use of RNAi
C) in vitro mutagenesis
D) in situ hybridization
E) restriction fragment analysis

Answer: C

A researcher has used in vitro mutagenesis to mutate a cloned gene and then has reinserted this into a cell. In order to have the mutated sequence disable the function of the gene, what must then occur?

A researcher has used in vitro mutagenesis to mutate a cloned gene and then has reinserted this into a cell. In order to have the mutated sequence disable the function of the gene, what must then occur? 

A) recombination resulting in replacement of the wild type with the mutated gene
B) use of a microarray to verify continued expression of the original gene
C) replication of the cloned gene using a bacterial plasmid
D) transcription of the cloned gene using a BAC
E) attachment of the mutated gene to an existing mRNA to be translated

Answer: A

RNAi methodology uses double-stranded pieces of RNA to trigger a breakdown or blocking of mRNA. For which of the following might it more possibly be useful?

RNAi methodology uses double-stranded pieces of RNA to trigger a breakdown or blocking of mRNA. For which of the following might it more possibly be useful? 

A) to raise the rate of production of a needed digestive enzyme
B) to decrease the production from a harmful gain-of-function mutated gene
C) to destroy an unwanted allele in a homozygous individual
D) to form a knockout organism that will not pass the deleted sequence to its progeny
E) to raise the concentration of a desired protein

Answer: B

Which uses reverse transcriptase to make cDNA followed by amplification?

Which uses reverse transcriptase to make cDNA followed by amplification? 

A) Southern blotting
B) Northern blotting
C) Western blotting
D) Eastern blotting
E) RT-PCR

Answer: E

Which describes the transfer of polypeptide sequences to a membrane to analyze gene expression?

Which describes the transfer of polypeptide sequences to a membrane to analyze gene expression?

A) Southern blotting
B) Northern blotting
C) Western blotting
D) Eastern blotting
E) RT-PCR

Answer: C

Which was developed by a British researcher and causes DNA sequences to be transferred to a membrane and identified with a probe?

Which was developed by a British researcher and causes DNA sequences to be transferred to a membrane and identified with a probe? 

A) Southern blotting
B) Northern blotting
C) Western blotting
D) Eastern blotting
E) RT-PCR

Answer: A

DNA microarrays have made a huge impact on genomic studies because they

DNA microarrays have made a huge impact on genomic studies because they 

A) can be used to eliminate the function of any gene in the genome.
B) can be used to introduce entire genomes into bacterial cells.
C) allow the expression of many or even all of the genes in the genome to be compared at once.
D) allow physical maps of the genome to be assembled in a very short time.
E) dramatically enhance the efficiency of restriction enzymes.

Answer: C

Dideoxyribonucleotide chain-termination is a method of

Dideoxyribonucleotide chain-termination is a method of 

A) cloning DNA.
B) sequencing DNA.
C) digesting DNA.
D) synthesizing DNA.
E) separating DNA fragments.



Answer: B

Which of the following procedures would produce RFLPs?

Which of the following procedures would produce RFLPs? 

A) incubating a mixture of single-stranded DNA from two closely related species
B) incubating DNA nucleotides with DNA polymerase
C) incubating DNA with restriction enzymes
D) incubating RNA with DNA nucleotides and reverse transcriptase
E) incubating DNA fragments with "sticky ends" with ligase

Answer: C

RFLP analysis can be used to distinguish between alleles based on differences in which of the following?

RFLP analysis can be used to distinguish between alleles based on differences in which of the following? 

A) restriction enzyme recognition sites between the alleles
B) the amount of DNA amplified from the alleles during PCR
C) the ability of the alleles to be replicated in bacterial cells
D) the proteins expressed from the alleles
E) the ability of nucleic acid probes to hybridize to the alleles

Answer: A

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?

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




Answer: A

Which of the following modifications is least likely to alter the rate at which a DNA fragment moves through a gel during electrophoresis?

Which of the following modifications is least likely to alter the rate at which a DNA fragment moves through a gel during electrophoresis? 

A) altering the nucleotide sequence of the DNA fragment
B) methylating the cytosine bases within the DNA fragment
C) increasing the length of the DNA fragment
D) decreasing the length of the DNA fragment
E) neutralizing the negative charges within the DNA fragment

Answer: A

In order to identify a specific restriction fragment using a probe, what must be done?

In order to identify a specific restriction fragment using a probe, what must be done? 

A) The fragments must be separated by electrophoresis.
B) The fragments must be treated with heat or chemicals to separate the strands of the double helix.
C) The probe must be hybridized with the fragment.
D) Only A and B are correct.
E) A, B, and C are correct.

Answer: E

Restriction fragments of DNA are typically separated from one another by which process?

Restriction fragments of DNA are typically separated from one another by which process? 

A) filtering
B) centrifugation
C) gel electrophoresis
D) PCR
E) electron microscopy




Answer: C

Which of the following separates molecules by movement due to size and electrical charge?

Which of the following separates molecules by movement due to size and electrical charge? 

A) restriction enzymes
B) gene cloning
C) DNA ligase
D) gel electrophoresis
E) reverse transcriptase

Answer: D

Which of the following cuts DNA molecules at specific locations?

Which of the following cuts DNA molecules at specific locations? 

A) restriction enzymes
B) gene cloning
C) DNA ligase
D) gel electrophoresis
E) reverse transcriptase

Answer: A

Which of the following is used to make complementary DNA (cDNA) from RNA?

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




Answer: E

Which of the following seals the sticky ends of restriction fragments to make recombinant DNA?

Which of the following seals the sticky ends of restriction fragments to make recombinant DNA? 

A) restriction enzymes
B) gene cloning
C) DNA ligase
D) gel electrophoresis
E) reverse transcriptase

Answer: C

Which of the following produces multiple identical copies of a gene for basic research or for large-scale production of a gene product?

Which of the following produces multiple identical copies of a gene for basic research or for large-scale production of a gene product? 

A) restriction enzymes
B) gene cloning
C) DNA ligase
D) gel electrophoresis
E) reverse transcriptase





Answer: B

The major advantage of using artificial chromosomes such as YACs and BACs for cloning genes is that

The major advantage of using artificial chromosomes such as YACs and BACs for cloning genes is that 

A) plasmids are unable to replicate in cells.
B) only one copy of a plasmid can be present in any given cell, whereas many copies of a YAC or BAC can coexist in a single cell.
C) YACs and BACs can carry much larger DNA fragments than ordinary plasmids can.
D) YACs and BACs can be used to express proteins encoded by inserted genes, but plasmids cannot.
E) all of the above

Answer: C

To introduce a particular piece of DNA into an animal cell, such as that of a mouse, you would find more probable success with which of the following methods?

To introduce a particular piece of DNA into an animal cell, such as that of a mouse, you would find more probable success with which of the following methods? 

A) the shotgun approach
B) electroporation followed by recombination
C) introducing a plasmid into the cell
D) infecting the mouse cell with a Ti plasmid
E) transcription and translation

Answer: B

Sequencing an entire genome, such as that of C. elegans, a nematode, is most important because

Sequencing an entire genome, such as that of C. elegans, a nematode, is most important because 

A) it allows researchers to use the sequence to build a "better" nematode, resistant to disease.
B) it allows research on a group of organisms we do not usually care much about.
C) the nematode is a good animal model for trying out cures for viral illness.
D) a sequence that is found to have a particular function in the nematode is likely to have a closely related function in vertebrates.
E) a sequence that is found to have no introns in the nematode genome is likely to have acquired the introns from higher organisms.

Answer: D

The first cell whose entire genome was sequenced was which of the following?

The first cell whose entire genome was sequenced was which of the following? 

A) H. influenzae in 1995
B) H. sapiens in 2001
C) rice in 1955
D) tobacco mosaic virus
E) HIV in 1998

Answer: A

A student wishes to clone a sequence of DNA of ~200 kb. Which vector would be appropriate?

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




Answer: C

A researcher needs to clone a sequence of part of a eukaryotic genome in order to express the sequence and to modify the polypeptide product. She would be able to satisfy these requirements by using which of the following vectors?

A researcher needs to clone a sequence of part of a eukaryotic genome in order to express the sequence and to modify the polypeptide product. She would be able to satisfy these requirements by using which of the following vectors? 

A) a bacterial plasmid
B) BAC to accommodate the size of the sequence
C) a modified bacteriophage
D) a human chromosome
E) a YAC with appropriate cellular enzymes

Answer: E

Which of the following best describes the complete sequence of steps occurring during every cycle of PCR?

Which of the following best describes the complete sequence of steps occurring during every cycle of PCR?

1. The primers hybridize to the target DNA.
2. The mixture is heated to a high temperature to denature the double stranded target DNA.
3. Fresh DNA polymerase is added.
4. DNA polymerase extends the primers to make a copy of the target DNA.



A) 2, 1, 4
B) 1, 3, 2, 4
C) 3, 4, 1, 2
D) 3, 4, 2
E) 2, 3, 4

Answer: A

Yeast artificial chromosomes contain which of the following elements?

Yeast artificial chromosomes contain which of the following elements? 

A) centromere only
B) telomeres only
C) origin of replication only
D) centromeres and telomeres only
E) centromere, telomeres, and an origin of replication

Answer: E

How does a genomic library differ from a cDNA library?

How does a genomic library differ from a cDNA library? 

A) A genomic library contains only noncoding sequences, whereas a cDNA library contains only coding sequences.
B) A genomic library varies, dependent on the cell type used to make it, whereas the content of a cDNA library does not.
C) A genomic library can be made using a restriction enzyme and DNA ligase only, whereas a cDNA library requires both of these as well as reverse transcriptase and DNA polymerase.
D) The genomic library can be replicated but not transcribed.
E) The genomic library contains only the genes that can be expressed in the cell.

Answer: C

The DNA fragments making up a genomic library are generally contained in

The DNA fragments making up a genomic library are generally contained in 

A) recombinant plasmids of bacteria.
B) recombinant viral RNA.
C) individual wells.
D) DNA-RNA hybrids
E) radioactive eukaryotic cells

Answer: A

Why are yeast cells frequently used as hosts for cloning?

Why are yeast cells frequently used as hosts for cloning? 

A) they easily form colonies
B) they can remove exons from mRNA.
C) they do not have plasmids.
D) they are eukaryotic cells
E) only yeast cells allow the gene to be cloned

Answer: D

A gene that contains introns can be made shorter (but remain functional) for genetic engineering purposes by using

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.

Answer: C

A principal problem with inserting an unmodified mammalian gene into a bacterial plasmid, and then getting that gene expressed in bacteria, is that

A principal problem with inserting an unmodified mammalian gene into a bacterial plasmid, and then getting that gene expressed in bacteria, is that 

A) prokaryotes use a different genetic code from that of eukaryotes.
B) bacteria translate polycistronic messages only.
C) bacteria cannot remove eukaryotic introns.
D) bacterial RNA polymerase cannot make RNA complementary to mammalian DNA.
E) bacterial DNA is not found in a membrane-bounded nucleus and is therefore incompatible with mammalian DNA.

Answer: C

Bacteria that do not take up any plasmids would grow on which media?

Bacteria that do not take up any plasmids would grow on which media? 

A) the nutrient broth only
B) the nutrient broth and the tetracycline broth
C) the nutrient broth and the ampicillin broth
D) the tetracycline broth and the ampicillin broth
E) all four broths

Answer: A

Bacteria containing a plasmid into which the eukaryotic gene has integrated would grow in

Bacteria containing a plasmid into which the eukaryotic gene has integrated would grow in 

A) the nutrient broth only.
B) the nutrient broth and the tetracycline broth only.
C) the nutrient broth, the ampicillin broth, and the tetracycline broth.
D) all four types of broth.
E) the ampicillin broth and the nutrient broth.

Answer: E

Bacteria that contain the plasmid, but not the eukaryotic gene, would grow

Bacteria that contain the plasmid, but not the eukaryotic gene, would grow 

A) in the nutrient broth plus ampicillin, but not in the broth containing tetracycline.
B) only in the broth containing both antibiotics.
C) in the broth containing tetracycline, but not in the broth containing ampicillin.
D) in all four types of broth.
E) in the nutrient broth without antibiotics only.

Answer: D

Bacteria containing recombinant plasmids are often identified by which process?

Bacteria containing recombinant plasmids are often identified by which process? 

A) examining the cells with an electron microscope
B) using radioactive tracers to locate the plasmids
C) exposing the bacteria to an antibiotic that kills cells lacking the resistant plasmid
D) removing the DNA of all cells in a culture to see which cells have plasmids
E) producing antibodies specific for each bacterium containing a recombinant plasmid

Answer: C

What is the most logical sequence of steps for splicing foreign DNA into a plasmid and inserting the plasmid into a bacterium?

What is the most logical sequence of steps for splicing foreign DNA into a plasmid and inserting the plasmid into a bacterium?

I. Transform bacteria with recombinant DNA molecule.
II. Cut the plasmid DNA using restriction enzymes.
III. Extract plasmid DNA from bacterial cells.
IV. Hydrogen-bond the plasmid DNA to nonplasmid DNA fragments.
V. Use ligase to seal plasmid DNA to nonplasmid DNA.



A) I, II, IV, III, V
B) II, III, V, IV, I
C) III, II, IV, V, I
D) III, IV, V, I, II
E) IV, V, I, II, III

Answer: C

How does a bacterial cell protect its own DNA from restriction enzymes?

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

Answer: A

What is the enzymatic function of restriction enzymes?

What is the enzymatic function of restriction enzymes? 

A) to add new nucleotides to the growing strand of DNA
B) to join nucleotides during replication
C) to join nucleotides during transcription
D) to cleave nucleic acids at specific sites
E) to repair breaks in sugar-phosphate backbones

Answer: D

Assume that you are trying to insert a gene into a plasmid. Someone gives you a preparation of genomic DNA that has been cut with restriction enzyme X. The gene you wish to insert has sites on both ends for cutting by restriction enzyme Y. You have a plasmid with a single site for Y, but not for X. Your strategy should be to

Assume that you are trying to insert a gene into a plasmid. Someone gives you a preparation of genomic DNA that has been cut with restriction enzyme X. The gene you wish to insert has sites on both ends for cutting by restriction enzyme Y. You have a plasmid with a single site for Y, but not for X. Your strategy should be to 

A) insert the fragments cut with X directly into the plasmid without cutting the plasmid.
B) cut the plasmid with restriction enzyme X and insert the fragments cut with Y into the plasmid.
C) cut the DNA again with restriction enzyme Y and insert these fragments into the plasmid cut with the same enzyme.
D) cut the plasmid twice with restriction enzyme Y and ligate the two fragments onto the ends of the DNA fragments cut with restriction enzyme X.
E) cut the plasmid with enzyme X and then insert the gene into the plasmid.

Answer: C

Which enzyme was used to produce the molecule in Figure 20.1?

Which enzyme was used to produce the molecule in Figure 20.1? 

A) ligase
B) transcriptase
C) a restriction enzyme
D) RNA polymerase
E) DNA polymerase

Answer: C

Most of the exchange surfaces of multicellular animals are lined with

Most of the exchange surfaces of multicellular animals are lined with

A) connective tissue.
B) smooth muscle cells.
C) neural tissue.
D) epithelial tissue.
E) adipose tissue.




Answer: D

The absorptive epithelia in the gut are considered "polarized" because

The absorptive epithelia in the gut are considered "polarized" because

A) thick and thin filaments are present.
B) they pump wastes into the lumen while pumping nutrients toward the blood.
C) the colors seen on the top and bottom of the cells are different.
D) they must fire action potentials to absorb most nutrients.
E) the structures on the apical surface are different than those on the basal surface.

Answer: E

Of the following choices, the epithelium with the shortest diffusion distance is

Of the following choices, the epithelium with the shortest diffusion distance is

A) simple squamous epithelium.
B) simple cuboidal epithelium.
C) simple columnar epithelium.
D) pseudostratified ciliated columnar epithelium.
E) stratified squamous epithelium.

Answer: A

An exchange surface in direct contact with the external environment is found in the

An exchange surface in direct contact with the external environment is found in the

A) lungs.
B) skeletal muscles.
C) liver.
D) heart.
E) brain.




Answer: A

Tissues are composed of cells, and tissues functioning together make up

Tissues are composed of cells, and tissues functioning together make up

A) organs.
B) membranes.
C) organ systems.
D) organelles.
E) organisms.

Answer: A

Multicellular organisms must keep their cells awash in an "internal pond" because

Multicellular organisms must keep their cells awash in an "internal pond" because

A) their membranes will crystallize if not in contact with interstitial fluid.
B) an aqueous medium is needed for the cellular exchange of nutrients, gases, and wastes.
C) this prevents the loss of water due to osmosis.
D) their cells need to be protected from dissolved nitrogen gas in the blood.
E) terrestrial organisms have not adapted to life in dry environments.

Answer: B

Interstitial fluid is

Interstitial fluid is

A) the fluid inside the gastrovascular cavity of Hydra.
B) the internal environment inside animal cells.
C) identical to the composition of blood.
D) the route for the exchange of materials between blood and body cells.
E) found only in the lumen of the small intestine.

Answer: D

The specialized function shared by the cells that line the lungs and those that line the lumen of the gut is that both types of cells

The specialized function shared by the cells that line the lungs and those that line the lumen of the gut is that both types of cells

A) receive their oxygen directly from inhaled air and ingested foods.
B) provide abundant exchange surface.
C) have exceptionally high numbers of cellular organelles in the cytoplasm.
D) offer greater protection due to increased membrane thickness.
E) have a lowered basal metabolic rate due to cooperative exchange between cells.

Answer: B

To increase the effectiveness of exchange surfaces lining the lungs and the intestines, evolutionary pressures have

To increase the effectiveness of exchange surfaces lining the lungs and the intestines, evolutionary pressures have

A) increased the exchange surface area with folds and branches.
B) increased the thickness of the membranes in these linings.
C) increased the number of cell layers in these linings.
D) decreased the metabolic rate of the cells in these linings.
E) increased the volume of the cells in these linings.

Answer: A

As body size increases in animals,

As body size increases in animals,

A) there is a decrease in the surface-to-volume ratio.
B) reproduction becomes limited to terrestrial environments.
C) there is greater variability in metabolic rate.
D) migration to tropical areas becomes necessary for thermoregulation.
E) it becomes more difficult to conserve body warmth in cold environments.

Answer: A

All animals, whether large or small, have

All animals, whether large or small, have

A) an external body surface that is dry.
B) a basic body plan that resembles a two-layered sac.
C) a body surface covered with hair to keep them warm.
D) the ability to enter dormancy when resources become scarce.
E) each living cell in contact with an aqueous medium.

Answer: E

The specialized structures of complex animals have evolved because

The specialized structures of complex animals have evolved because

A) the environment imposes identical problems regardless of where the animals are found.
B) the development of the specialized structures in an animal is influenced by the animal's ability to learn.
C) the simplest animals are those with the most recent appearance among the biota.
D) they permit adjustments to a wide range of environmental changes.
E) the most complex animals are the ones with the most ancient evolutionary origin.

Answer: D

The similar fusiform body shape of diverse animals, such as sharks, penguins, and aquatic mammals, has evolved because

The similar fusiform body shape of diverse animals, such as sharks, penguins, and aquatic mammals, has evolved because

A) natural selection typically has no limits when different organisms face the same challenge.
B) respiration through gills is enhanced by having a fusiform shape.
C) this is the body shape that makes it possible for aquatic animals to swim rapidly.
D) the fusiform shape is coded by the same genes in all three types of aquatic animals.
E) all three types evolved from the same ancestral form, which flew in air rather than swam in water.






Answer: C

Evolutionary adaptations that help diverse animals directly exchange matter between cells and the environment include

Evolutionary adaptations that help diverse animals directly exchange matter between cells and the environment include

A) a gastrovascular activity, a two-layered body, and a torpedo-like body shape.
B) an external respiratory surface, a small body size, and a two-cell-layered body.
C) a large body volume; a long, tubular body; and a set of wings.
D) complex internal structures, a small body size, and a large surface area.
E) an unbranched internal surface, a small body size, and thick covering.

Answer: B

Penguins, seals, and tuna have body forms that permit rapid swimming, because

Penguins, seals, and tuna have body forms that permit rapid swimming, because

A) all share a common ancestor at some point in the past.
B) all of their bodies have been compressed since birth by intensive underwater pressures.
C) flying, pregnancy, and gill-breathing all require similar adaptations in form.
D) the shape is a convergent evolutionary solution to the need to reduce drag while swimming.
E) this is the only shape that will allow them to maintain a constant body temperature in water.

Answer: D

Which choice best describes a reasonable mechanism for animal structures becoming better suited over evolutionary time to specific functions?

Which choice best describes a reasonable mechanism for animal structures becoming better suited over evolutionary time to specific functions?

A) Animals that eat the most food become the most abundant.
B) Animals that restrict their food intake will become less abundant.
C) Animals with mutations that give rise to effective structures will become more abundant.
D) Animals with inventions that curtail reproduction will become more abundant.
E) Animals with parents that continually improve their offspring's structures will become more abundant.

Answer: C

If thermoregulation is considered to be a secondary function of the large ears of jackrabbits, then the primary function of the ears is

If thermoregulation is considered to be a secondary function of the large ears of jackrabbits, then the primary function of the ears is

A) to optimize nutrient intake through the thin, permeable surfaces on the ears.
B) to alter the rate of gas exchange, based on the adjustable radius of the ears' blood vessels.
C) to detect predators by using the large size and flexible positioning of the external ears to channel sound waves into the ear canal.
D) to protect offspring from bright sunlight by the positioning of the ears to cast the maximum shadows.
E) to protect against pathogens by having a thick, waxy surface on the ears.

Answer: C

When the temperature of the outside air exceeds their internal body temperature, jackrabbits living in hot, arid lands will

When the temperature of the outside air exceeds their internal body temperature, jackrabbits living in hot, arid lands will

A) dilate the blood vessels in their large ears to transfer more body heat to the environment.
B) constrict the blood vessels in their large ears to reduce transfer of external heat to the blood in their ears.
C) increase motor movements to find a sunny area to maximize heat transfer into their bodies.
D) increase pigmentation in their ears, darkening them to maximize their capacity to take up heat.
E) begin involuntary shivering of their skeletal muscles in order to generate more metabolic heat.

Answer: B

Which of the following characteristics indicates that mollusks are more closely related to arthropods than to chordates?

Which of the following characteristics indicates that mollusks are more closely related to arthropods than to chordates?

A) Presence of a skeleton
B) Type of respiratory structure
C) Pattern of coelom formation
D) Segmentation
E) Symmetry

Answer: B

Many parasitic flatworms have an intermediate host. This indicates that the

Many parasitic flatworms have an intermediate host. This indicates that the

A) flatworms cannot infect humans
B) larval flatworms infect one species, whereas adults infect another species
C) larval flatworms infect only juveniles of a species
D) flatworm adults are microscopic
E) flatworm larvae are parasitic on their parents

Answer: B

Members of which of the following animal groups were among the first to inhabit land and were ancestors of the reptiles?

Members of which of the following animal groups were among the first to inhabit land and were ancestors of the reptiles?

A) Amphibia
B) Arthropoda
C) Aves
D) Mammalia
E) Echinodermata

Answer: A

In animals, all of the following are associated with embryonic development EXCEPT

In animals, all of the following are associated with embryonic development EXCEPT

A) migration of cells to specific areas
B) formation of germ layers
C) activation of all the genes in each cell
D) inductive tissue interactions
E) cell division at a relatively rapid rate

Answer: C

All of the following are deuterostomes EXCEPT

All of the following are deuterostomes EXCEPT

A) mollusks
B) reptiles
C) amphibians
D) echinoderms
E) mammals

Answer: A

In a mammalian embryo, the somites give rise to

In a mammalian embryo, the somites give rise to

A) the notochord
B) the central nervous system
C) the lining of the mouth
D) the eyes
E) muscles and vertebrae

Answer: E

If an invertebrate possesses nephridia as an excretory system, skin as a gas exchange system, and a closed circulatory system, the animal is most likely to be

If an invertebrate possesses nephridia as an excretory system, skin as a gas exchange system, and a closed circulatory system, the animal is most likely to be

A) a snail
B) a planarian
C) an earthworm
D) a grasshopper
E) a jellyfish

Answer: C

Which of the following describes the correct sequence of stages during embryogenesis?

Which of the following describes the correct sequence of stages during embryogenesis?

A) Cleavage, blastula formation, gastrulation
B) Cleavage, gastrulation, blastula formation
C) Blastula formation, gastrulation, cleavage
D) Blastula formation, cleavage, gastrulation
E) Gastrulation, cleavage, blastula formation

Answer: A

Which process establishes the primary germ layers.

Which process establishes the primary germ layers.

Answer: Gastrulation

Vertebrates became truly terrestrial with the development of the amniotic egg in

Vertebrates became truly terrestrial with the development of the amniotic egg in

A) Fish
B) Amphibians
C) Reptiles
D) Birds
E) Mammals

Answer: C

The drug cytochalasin B blocks the function of actin. Which of the following aspects of the cell cycle would be most disrupted by cytochalasin B?

The drug cytochalasin B blocks the function of actin. Which of the following aspects of the cell cycle would be most disrupted by cytochalasin B? 

A) spindle formation
B) spindle attachment to kinetochores
C) DNA synthesis
D) cell elongation during anaphase
E) cleavage furrow formation and cytokinesis





Answer: E

A particular cell has half as much DNA as some other cells in a mitotically active tissue. The cell in question is most likely in

A particular cell has half as much DNA as some other cells in a mitotically active tissue. The cell in question is most likely in 

A) G1.
B) G2.
C) prophase.
D) metaphase.
E) anaphase.




Answer: A

Which of the following does not occur during mitosis?

Which of the following does not occur during mitosis? 

A) condensation of the chromosomes
B) replication of the DNA
C) separation of sister chromatids
D) spindle formation
E) separation of the spindle poles


Answer: B

In the cells of some organisms, mitosis occurs without cytokinesis. This will result in

In the cells of some organisms, mitosis occurs without cytokinesis. This will result in 

A) cells with more than one nucleus.
B) cells that are unusually small.
C) cells lacking nuclei.
D) destruction of chromosomes.
E) cell cycles lacking an S phase.





Answer: A

The decline of MPF activity at the end of mitosis is due to

The decline of MPF activity at the end of mitosis is due to 

A) the destruction of the protein kinase Cdk.
B) decreased synthesis of Cdk.
C) the degradation of cyclin.
D) the accumulation of cyclin.
E) synthesis of DNA.






Answer: C

One difference between cancer cells and normal cells is that cancer cells

One difference between cancer cells and normal cells is that cancer cells 

A) are unable to synthesize DNA.
B) are arrested at the S phase of the cell cycle.
C) continue to divide even when they are tightly packed together.
D) cannot function properly because they are affected by density-dependent inhibition.
E) are always in the M phase of the cell cycle.





Answer: C

Vinblastine is a standard chemotherapeutic drug used to treat cancer. Because it interferes with the assembly of microtubules, its effectiveness must be related to

Vinblastine is a standard chemotherapeutic drug used to treat cancer. Because it interferes with the assembly of microtubules, its effectiveness must be related to 

A) disruption of mitotic spindle formation.
B) inhibition of regulatory protein phosphorylation.
C) suppression of cyclin production.
D) myosin denaturation and inhibition of cleavage furrow formation.
E) inhibition of DNA synthesis.




Answer: A

Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on either side of the cell plate. This cell is most likely

Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on either side of the cell plate. This cell is most likely 

A) an animal cell in the process of cytokinesis.
B) a plant cell in the process of cytokinesis.
C) an animal cell in the S phase of the cell cycle.
D) a bacterial cell dividing.
E) a plant cell in metaphase.




Answer: B

A student is looking through his light microscope (~450 X) at a squashed and stained onion root tip. Some, but not all, of the cells have clearly visible chromosome strands.

When a cell is in anaphase of mitosis, which of the following will he see? 

A) a clear area in the center of the cell
B) chromosomes clustered at the poles
C) individual chromatids separating
D) chromosomes clustered tightly at the center
E) formation of vesicles at the midline

Answer: A

When the cell has just completed telophase, which of the following does he see? 

A) a clear area in the center of the cell
B) chromosomes clustered at the poles
C) individual chromatids separating
D) formation of vesicles at the midline
E) two small cells with chromatin

Answer: E

The research team established similar lymphocyte cultures from a number of human donors, including healthy teenagers of both genders, patients already suffering from long-term bacterial infections, and elderly volunteers. They found that the increase in lymphocyte incorporation after pathogen introduction was slightly lower in some of the female teenagers and significantly lower in each of the elderly persons. They repeated the study with a larger number of samples but got the same results.

What might be among the research team's conclusions? 

A) The young women showed these results because they have poorer nutrition.
B) The elderly persons' samples demonstrated their lowered immune responses.
C) The young men had higher responses because they are generally healthier.
D) The patient samples should have had the lowest response but did not, so the experiment is invalid.
E) The elderly donor samples represent cells no longer capable of any cell division.


Answer: B

Which of the following investigations might be most productive to show what the data on the teenagers might indicate? 

A) test male teenagers
B) test teenagers who say they are not sexually active
C) test female teens at different times in their menstrual cycles
D) test relatives of the teens previously tested
E) test teenagers from different school systems

Answer: C

Nucleotides can be radiolabeled before they are incorporated into newly forming DNA and can therefore be assayed to track their incorporation. In a set of experiments, a student—faculty research team used labeled T nucleotides and introduced these into the culture of dividing human cells at specific times.

Which of the following questions might be answered by such a method?

A) How many cells are produced by the culture per hour?
B) What is the length of the S phase of the cell cycle?
C) When is the S chromosome synthesized?
D) How many picograms of DNA are made per cell cycle?
E) When do spindle fibers attach to chromosomes?


Answer: B

The research team used the setup to study the incorporation of labeled nucleotides into a culture of lymphocytes and found that the lymphocytes incorporated the labeled nucleotide at a significantly higher level after a pathogen was introduced into the culture. They concluded that 

A) the presence of the pathogen made the experiment too contaminated to trust the results.
B) their tissue culture methods needed to be relearned.
C) infection causes lymphocytes to divide more rapidly.
D) infection causes cell cultures in general to reproduce more rapidly.
E) infection causes lymphocyte cultures to skip some parts of the cell cycle.


Answer: C

Once they had determined which cells were dividing, the team wanted to use a non-radioactive method to track whether various physiological factors (such as food or body temperature) affect the action of the pathogen. Which of the following would be effective, simple, and safe? 

A) measuring picograms of DNA
B) measuring numbers of chromosomes
C) measuring numbers of chromatids
D) counting the frequency of cells in mitosis
E) counting newly formed plasma membranes



Answer: D

Several organisms, primarily protists, have what are called intermediate mitotic organization.

Several organisms, primarily protists, have what are called intermediate mitotic organization. 

These protists are intermediate in what sense? 

A) They reproduce by binary fission in their early stages of development and by mitosis when they are mature.
B) They never coil up their chromosomes when they are dividing.
C) They use mitotic division but only have circular chromosomes.
D) They maintain a nuclear envelope during division.
E) None of them form spindles.

Answer: D

Several organisms, primarily protists, have what are called intermediate mitotic organization. 

A) They represent a form of cell reproduction which must have evolved completely separately from those of other organisms.
B) They demonstrate that these species are not closely related to any of the other protists and may well be a different kingdom.
C) They rely on totally different proteins for the processes they undergo.
D) They may be more closely related to plant forms that also have unusual mitosis.
E) They show some but not all of the evolutionary steps toward complete mitosis.



Answer: E

MPF reaches its threshold concentration at the end of this stage.

MPF reaches its threshold concentration at the end of this stage. 

A) I
B) II
C) III
D) IV
E) V






Answer: C

At which of the numbered regions would you expect to find cells at metaphase?

At which of the numbered regions would you expect to find cells at metaphase? 

A) I and IV
B) II only
C) III only
D) IV only
E) V only


Answer: C

Which number represents the point in the cell cycle during which the chromosomes are replicated?

Which number represents the point in the cell cycle during which the chromosomes are replicated? 

A) I
B) II
C) III
D) IV
E) V





Answer: B

Which number represents DNA synthesis?

Which number represents DNA synthesis? 

A) I
B) II
C) III
D) IV
E) V





Answer: B

G1 is represented by which numbered part(s) of the cycle?

G1 is represented by which numbered part(s) of the cycle? 

A) I or V
B) II or IV
C) III only
D) IV only
E) V only





Answer: A

If the cell whose nuclear material is shown in Figure 12.2 continues toward completion of mitosis, which of the following events would occur next?

If the cell whose nuclear material is shown in Figure 12.2 continues toward completion of mitosis, which of the following events would occur next? 

A) cell membrane synthesis
B) spindle fiber formation
C) nuclear envelope breakdown
D) formation of telophase nuclei
E) synthesis of chromatids



Answer: D

What is the correct chromosomal condition at the prometaphase of mitosis?

The lettered circle in Figure 12.1 shows a diploid nucleus with four chromosomes. There are two pairs of homologous chromosomes, one long and the other short. One haploid set is symbolized as black and the other haploid set is gray. The chromosomes in the unlettered circle have not yet replicated. Choose the correct chromosomal conditions for the following stages.

What is the correct chromosomal condition at the prometaphase of mitosis? 

A) A
B) B
C) C
D) D
E) E




Answer: B

You have a series of cells, all of which were derived from tumors, and you first need to find out which ones are malignant. What could you do?

You have a series of cells, all of which were derived from tumors, and you first need to find out which ones are malignant. What could you do? 

A) See which ones are not over proliferating.
B) Find out which ones have a higher rate of apoptosis.
C) Karyotype samples to look for unusual size and number of chromosomes.
D) Measure metastasis.
E) Time their cell cycles.




Answer: C

For a chemotherapeutic drug to be useful for treating cancer cells, which of the following is most desirable?

For a chemotherapeutic drug to be useful for treating cancer cells, which of the following is most desirable? 

A) It is safe enough to limit all apoptosis.
B) It does not alter metabolically active cells.
C) It only attacks cells that are density dependent.
D) It interferes with cells entering G0.
E) It interferes with rapidly dividing cells.





Answer: E

A research team began a study of a cultured cell line. Their preliminary observations showed them that the cell line did not exhibit either density-dependent inhibition or anchorage dependence. What could they conclude right away?

A research team began a study of a cultured cell line. Their preliminary observations showed them that the cell line did not exhibit either density-dependent inhibition or anchorage dependence. What could they conclude right away? 

A) The cells originated in the nervous system.
B) The cells are unable to form spindle microtubules.
C) They have altered series of cell cycle phases.
D) The cells show characteristics of tumors.
E) They were originally derived from an elderly organism.




Answer: D

What explains anchorage dependence of animal cells in vitro or in vivo?

What explains anchorage dependence of animal cells in vitro or in vivo? 

A) attachment of spindle fibers to centrioles
B) response of the plasma membrane to cell cycle controls
C) the makeup of the extracellular matrix of the substrate
D) the binding of cell-surface phospholipids to those of adjoining cells
E) the binding of cell-surface phospholipids to the substrate






Answer: B

At the M phase checkpoint, the complex allows for what to occur?

At the M phase checkpoint, the complex allows for what to occur? 

A) Separase enzyme cleaves cohesins and allows chromatids to separate.
B) Cohesins alter separase to allow chromatids to separate.
C) Kinetochores are able to bind to spindle microtubules.
D) All microtubules are made to bind to kinetochores.
E) Daughter cells are allowed to pass into G1.





Answer: A

All cell cycle checkpoints are similar in which way?

All cell cycle checkpoints are similar in which way? 

A) They respond to the same cyclins.
B) They utilize the same Cdks.
C) They give the go-ahead signal to progress to the next checkpoint.
D) They each have only one cyclin/Cdk complex.
E) They activate or inactivate other proteins.




Answer: E

Which of the following most accurately describes a cyclin?

Which of the following most accurately describes a cyclin? 

A) It is present in similar concentrations throughout the cell cycle.
B) It is activated to phosphorylate by complexing with a Cdk.
C) It decreases in concentration when MPF activity increases.
D) It activates a Cdk molecule when it is in sufficient concentration.
E) It activates a Cdk when its concentration is decreased.




Answer: D

Why do neurons and some other specialized cells divide infrequently?

Why do neurons and some other specialized cells divide infrequently? 

A) They no longer have active nuclei.
B) They no longer carry receptors for signal molecules.
C) They have been shunted into G0.
D) They can no longer bind Cdk to cyclin.
E) They show a drop in MPF concentration.

Answer: C

After which checkpoint is the cell first committed to continue the cell cycle through M?

After which checkpoint is the cell first committed to continue the cell cycle through M? 

A) G0
B) G1
C) G2
D) S
E) previous M





Answer: B

Besides the ability of some cancer cells to overproliferate, what else could logically result in a tumor?

Besides the ability of some cancer cells to overproliferate, what else could logically result in a tumor? 

A) metastasis
B) changes in the order of cell cycle stages
C) lack of appropriate cell death
D) inability to form spindles
E) inability of chromosomes to meet at the metaphase plate




Answer: C

Cells from an advanced malignant tumor most often have very abnormal chromosomes, and often an abnormal total number of chromosomes. Why might this occur?

Cells from an advanced malignant tumor most often have very abnormal chromosomes, and often an abnormal total number of chromosomes. Why might this occur? 

A) Cancer cells are no longer density dependent.
B) Cancer cells are no longer anchorage dependent.
C) Chromosomally abnormal cells can still go through cell cycle checkpoints.
D) Chromosomally abnormal cells still have normal metabolism.
E) Transformation introduces new chromosomes into cells.



Answer: C

A particular cyclin called cyclin E forms a complex with Cdk 2 (cyclin-dependent kinase 2). This complex is important for the progression of the cell from G1 into the S phase of the cell cycle. Which of the following statements is correct?

A particular cyclin called cyclin E forms a complex with Cdk 2 (cyclin-dependent kinase 2). This complex is important for the progression of the cell from G1 into the S phase of the cell cycle. Which of the following statements is correct? 

A) The amount of free cyclin E is greatest during the S phase.
B) The amount of free Cdk 2 is greater during G1 compared to the S phase.
C) The amount of free cyclin E is highest during G1.
D) The amount of free Cdk 2 is greatest during G1.
E) The activity of the cyclin E/Cdk 2 complex is highest during G2.




Answer: C

Which of the following describe(s) cyclin-dependent kinase (Cdk)?

Which of the following describe(s) cyclin-dependent kinase (Cdk)? 

A) Cdk is inactive, or "turned off," in the presence of cyclin.
B) Cdk is present throughout the cell cycle.
C) Cdk is an enzyme that attaches phosphate groups to other proteins.
D) Cdk is inactive, or "turned off," in the presence of cyclin and it is present throughout the cell cycle.
E) Cdk is present throughout the cell cycle and is an enzyme that attaches phosphate groups to other proteins.

Answer: E

Which of the following is true concerning cancer cells?

Which of the following is true concerning cancer cells? 

A) They do not exhibit density-dependent inhibition when growing in culture.
B) When they stop dividing, they do so at random points in the cell cycle.
C) They are not subject to cell cycle controls.
D) When they stop dividing, they do so at random points in the cell cycle, and they are not subject to cell cycle controls.
E) When they stop dividing, they do so at random points in the cell cycle; they are not subject to cell cycle controls; and they do not exhibit density-dependent inhibition when growing in culture.

Answer: E

Density-dependent inhibition is explained by which of the following?

Density-dependent inhibition is explained by which of the following? 

A) As cells become more numerous, they begin to squeeze against each other, restricting their size and ability to produce control factors.
B) As cells become more numerous, the cell surface proteins of one cell contact the adjoining cells and they stop dividing.
C) As cells become more numerous, the protein kinases they produce begin to compete with each other, such that the proteins produced by one cell essentially cancel those produced by its neighbor.
D) As cells become more numerous, more and more of them enter the S phase of the cell cycle.
E) As cells become more numerous, the level of waste products increases, eventually slowing down metabolism.

Answer: B

A mutation results in a cell that no longer produces a normal protein kinase for the M phase checkpoint. Which of the following would likely be the immediate result of this mutation?

A mutation results in a cell that no longer produces a normal protein kinase for the M phase checkpoint. Which of the following would likely be the immediate result of this mutation? 

A) The cell would prematurely enter anaphase.
B) The cell would never leave metaphase.
C) The cell would never enter metaphase.
D) The cell would never enter prophase.
E) The cell would undergo normal mitosis, but fail to enter the next G1 phase.

Answer: E

The MPF protein complex turns itself off by

The MPF protein complex turns itself off by 

A) activating a process that destroys cyclin components.
B) activating an enzyme that stimulates cyclin.
C) binding to chromatin.
D) exiting the cell.
E) activating the anaphase-promoting complex.




Answer: A

Proteins that are involved in the regulation of the cell cycle, and that show fluctuations in concentration during the cell cycle, are called

Proteins that are involved in the regulation of the cell cycle, and that show fluctuations in concentration during the cell cycle, are called 

A) ATPases.
B) kinetochores.
C) kinases.
D) proton pumps.
E) cyclins.







Answer: E

The cyclin component of MPF is destroyed toward the end of which phase?

The cyclin component of MPF is destroyed toward the end of which phase? 

A) G0
B) G1
C) S
D) G2
E) M






Answer: E

Which of the following triggers the cell's passage past the G2 checkpoint into mitosis?

Which of the following triggers the cell's passage past the G2 checkpoint into mitosis? 

A) PDGF
B) MPF
C) protein kinase
D) cyclin
E) Cdk





Answer: B

Which of the following is a protein maintained at constant levels throughout the cell cycle that requires cyclin to become catalytically active?

Which of the following is a protein maintained at constant levels throughout the cell cycle that requires cyclin to become catalytically active? 

A) PDGF
B) MPF
C) protein kinase
D) cyclin
E) Cdk






Answer: E

Which of the following is a protein synthesized at specific times during the cell cycle that associates with a kinase to form a catalytically active complex?

Which of the following is a protein synthesized at specific times during the cell cycle that associates with a kinase to form a catalytically active complex? 

A) PDGF
B) MPF
C) protein kinase
D) cyclin
E) Cdk






Answer: D

Which of the following is released by platelets in the vicinity of an injury?

Which of the following is released by platelets in the vicinity of an injury? 

A) PDGF
B) MPF
C) protein kinase
D) cyclin
E) Cdk





Answer: A

What causes the decrease in the amount of cyclin at a specific point in the cell cycle?

What causes the decrease in the amount of cyclin at a specific point in the cell cycle? 

A) an increase in production once the restriction point is passed
B) the cascade of increased production once its protein is phosphorylated by Cdk
C) the changing ratio of cytoplasm to genome
D) its destruction by a process initiated by the activity of its complex with a cyclin
E) the binding of PDGF to receptors on the cell surface





Answer: D

A plant-derived protein known as colchicine can be used to poison cells by blocking the formation of the spindle. Which of the following would result if colchicine is added to a sample of cells in G2?

A plant-derived protein known as colchicine can be used to poison cells by blocking the formation of the spindle. Which of the following would result if colchicine is added to a sample of cells in G2? 

A) The cells would immediately die.
B) The cells would be unable to begin M and stay in G2.
C) The chromosomes would coil and shorten but have no spindle to which to attach.
D) The chromosomes would segregate but in a disorderly pattern.
E) Each resultant daughter cell would also be unable to form a spindle.





Answer: C

You have the technology necessary to measure each of the following in a sample of animal cells: chlorophylls, organelle density, picograms of DNA, cell wall components, and enzymatic activity. Which would you expect to increase significantly from M to G1?

You have the technology necessary to measure each of the following in a sample of animal cells: chlorophylls, organelle density, picograms of DNA, cell wall components, and enzymatic activity. Which would you expect to increase significantly from M to G1? 

A) organelle density and enzymatic activity
B) cell wall components and DNA
C) chlorophyll and cell walls
D) organelle density and cell walls
E) chlorophyll and DNA




Answer: A

Using which of the following techniques would enable your lab group to distinguish between a cell in G2 and a cell from the same organism in G1?

Using which of the following techniques would enable your lab group to distinguish between a cell in G2 and a cell from the same organism in G1? 

A) fluorescence microscopy
B) electron microscopy
C) spectrophotometry
D) radioactive-labeled nucleotides
E) labeled kinetochore proteins





Answer: D

Which of the following proteins are involved in binary fission as well as eukaryotic mitotic division?

Which of the following proteins are involved in binary fission as well as eukaryotic mitotic division? 

A) cyclins
B) Cdks
C) MPF
D) actin and tubulin
E) cohesins





Answer: D

What is a cleavage furrow?

What is a cleavage furrow? 

A) a ring of vesicles forming a cell plate
B) the separation of divided prokaryotes
C) a groove in the plasma membrane between daughter nuclei
D) the metaphase plate where chromosomes attach to the spindle
E) the space that is created between two chromatids during anaphase





Answer: C

Which of the following is (are) required for motor proteins to function in the movement of chromosomes toward the poles of the mitotic spindle?

Which of the following is (are) required for motor proteins to function in the movement of chromosomes toward the poles of the mitotic spindle?

A) intact centromeres
B) an MTOC (microtubule organizing center)
C) a kinetochore attached to the metaphase plate
D) ATP as an energy source
E) synthesis of cohesin





Answer: D

Which of the following was a discovery that had to be made before human chromosomes could be correctly counted?

Which of the following was a discovery that had to be made before human chromosomes could be correctly counted? 

A) how to use a hypotonic solution to swell nuclei
B) how to visualize sperm nuclei
C) how to visualize chromosomes
D) when to see chromosomes separate from one another
E) when to see chromosomes in pairs





Answer: A

During which phase of mitosis do the chromatids become chromosomes?

During which phase of mitosis do the chromatids become chromosomes? 

A) telophase
B) anaphase
C) prophase
D) metaphase
E) cytokinesis






Answer: A

Which of the following is a function of those spindle microtubules that do not attach to kinetochores?

Which of the following is a function of those spindle microtubules that do not attach to kinetochores? 

A) maintaining an appropriate spacing among the moving chromosomes
B) producing a cleavage furrow when telophase is complete
C) providing the ATP needed by the fibers attached to kinetochores
D) maintaining the region of overlap of microtubules in the cell's center
E) pulling the poles of the spindles closer to one another

Answer: D

Which of the following best describes how chromosomes move toward the poles of the spindle during mitosis?

Which of the following best describes how chromosomes move toward the poles of the spindle during mitosis? 

A) The chromosomes are "reeled in" by the contraction of spindle microtubules.
B) Motor proteins of the kinetochores move the chromosomes along the spindle microtubules.
C) Nonkinetochore spindle fibers serve to push chromosomes in the direction of the poles.
D) The chromosomes are "reeled in" by the contraction of spindle microtubules, and motor proteins of the kinetochores move the chromosomes along the spindle microtubules.
E) The chromosomes are "reeled in" by the contraction of spindle microtubules, motor proteins of the kinetochores move the chromosomes along the spindle microtubules, and nonkinetochore spindle fibers serve to push chromosomes in the direction of the poles.

Answer: D

Why do chromosomes coil during mitosis?

Why do chromosomes coil during mitosis? 

A) to increase their potential energy
B) to allow the chromosomes to move without becoming entangled and breaking
C) to allow the chromosomes to fit within the nuclear envelope
D) to allow the sister chromatids to remain attached
E) to provide for the structure of the centromere





Answer: B

For anaphase to begin, which of the following must occur?

For anaphase to begin, which of the following must occur? 

A) Chromatids must lose their kinetochores.
B) Cohesin must attach the sister chromatids to each other.
C) Cohesin must be cleaved enzymatically.
D) Kinetochores must attach to the metaphase plate.
E) Spindle microtubules must begin to depolymerize.





Answer: C

A group of cells is assayed for DNA content immediately following mitosis and is found to have an average of 8 picograms of DNA per nucleus. How many picograms would be found at the end of S and the end of G2?

A group of cells is assayed for DNA content immediately following mitosis and is found to have an average of 8 picograms of DNA per nucleus. How many picograms would be found at the end of S and the end of G2? 

A) 8; 8
B) 8; 16
C) 16; 8
D) 16; 16
E) 12; 16





Answer: D

Measurements of the amount of DNA per nucleus were taken on a large number of cells from a growing fungus. The measured DNA levels ranged from 3 to 6 picograms per nucleus. In which stage of the cell cycle did the nucleus contain 6 picograms of DNA?

Measurements of the amount of DNA per nucleus were taken on a large number of cells from a growing fungus. The measured DNA levels ranged from 3 to 6 picograms per nucleus. In which stage of the cell cycle did the nucleus contain 6 picograms of DNA? 

A) G0
B) G1
C) S
D) G2
E) M





Answer: D

Movement of the chromosomes during anaphase would be most affected by a drug that

Movement of the chromosomes during anaphase would be most affected by a drug that 

A) reduces cyclin concentrations.
B) increases cyclin concentrations.
C) prevents elongation of microtubules.
D) prevents shortening of microtubules.
E) prevents attachment of the microtubules to the kinetochore.





Answer: D

In which group of eukaryotic organisms does the nuclear envelope remain intact during mitosis?

In which group of eukaryotic organisms does the nuclear envelope remain intact during mitosis? 

A) seedless plants
B) dinoflagellates
C) diatoms
D) dinoflagellates and diatoms only
E) seedless plants, dinoflagellates, and diatoms





Answer: D

Which of the following are primarily responsible for cytokinesis in plant cells but not in animal cells?

Which of the following are primarily responsible for cytokinesis in plant cells but not in animal cells? 

A) kinetochores
B) Golgi-derived vesicles
C) actin and myosin
D) centrioles and centromeres
E) cyclin-dependent kinases





Answer: B

Taxol is an anticancer drug extracted from the Pacific yew tree. In animal cells, Taxol disrupts microtubule formation by binding to microtubules and accelerating their assembly from the protein precursor, tubulin. Surprisingly, this stops mitosis. Specifically, Taxol must affect

Taxol is an anticancer drug extracted from the Pacific yew tree. In animal cells, Taxol disrupts microtubule formation by binding to microtubules and accelerating their assembly from the protein precursor, tubulin. Surprisingly, this stops mitosis. Specifically, Taxol must affect 

A) the formation of the mitotic spindle.
B) anaphase.
C) formation of the centrioles.
D) chromatid assembly.
E) the S phase of the cell cycle.





Answer: A

Where do the microtubules of the spindle originate during mitosis in both plant and animal cells?

Where do the microtubules of the spindle originate during mitosis in both plant and animal cells? 

A) centromere
B) centrosome
C) centriole
D) chromatid
E) kinetochore






Answer: B

If there are 20 centromeres in a cell at anaphase, how many chromosomes are there in each daughter cell following cytokinesis?

If there are 20 centromeres in a cell at anaphase, how many chromosomes are there in each daughter cell following cytokinesis? 

A) 10
B) 20
C) 30
D) 40
E) 80





Answer: A

If cells in the process of dividing are subjected to colchicine, a drug that interferes with the formation of the spindle apparatus, at which stage will mitosis be arrested?

If cells in the process of dividing are subjected to colchicine, a drug that interferes with the formation of the spindle apparatus, at which stage will mitosis be arrested? 

A) anaphase
B) prophase
C) telophase
D) metaphase
E) interphase





Answer: D

At which phase are centrioles beginning to move apart in animal cells?

At which phase are centrioles beginning to move apart in animal cells? 

A) telophase
B) anaphase
C) prometaphase
D) metaphase
E) prophase




Answer: E

Suppose a biologist can separate one of a dozen pieces of chromatin from a eukaryotic (animal) nucleus. It might consist of which of the following?

Suppose a biologist can separate one of a dozen pieces of chromatin from a eukaryotic (animal) nucleus. It might consist of which of the following?

A) one-twelfth of the genes of the organism
B) two chromosomes, each with six chromatids
C) a single circular piece of DNA
D) two long strands of DNA plus proteins
E) two chromatids attached together at a centromere




Answer: D

For a newly evolving protist, what would be the advantage of using eukaryote-like cell division rather than binary fission?

For a newly evolving protist, what would be the advantage of using eukaryote-like cell division rather than binary fission? 

A) Binary fission would not allow for the formation of new organisms.
B) Cell division would allow for the orderly and efficient segregation of multiple linear chromosomes.
C) Cell division would be faster than binary fission.
D) Cell division allows for lower rates of error per chromosome replication.
E) Binary fission would not allow the organism to have complex cells.



Answer: B

If there are 20 chromatids in a cell, how many centromeres are there?

If there are 20 chromatids in a cell, how many centromeres are there? 

A) 10
B) 20
C) 30
D) 40
E) 80




Answer: A

Starting with a fertilized egg (zygote), a series of five cell divisions would produce an early embryo with how many cells?

Starting with a fertilized egg (zygote), a series of five cell divisions would produce an early embryo with how many cells? 

A) 4
B) 8
C) 16
D) 32
E) 64





Answer: D

The centromere is a region in which

The centromere is a region in which 

A) chromatids remain attached to one another until anaphase.
B) metaphase chromosomes become aligned at the metaphase plate.
C) chromosomes are grouped during telophase.
D) the nucleus is located prior to mitosis.
E) new spindle microtubules form at either end.




Answer: A