chapter 20 human bio

All of the following statements about transgenic plants are true, EXCEPT that __________. a. human genes cannot be incorporated into transgenic plants b. transgenic plants have been developed that are resistant to pests such as larval insects c. genes have been successfully introduced into plants to improve the nutritional value d. transgenic plants are being studied as a way to produce edible vaccines

a

One concern regarding the use of transgenic plants is the __________. a. loss of crop biodiversity, leading to potential widespread crop failures b. documentation of serious adverse health effects from transgenic products in the United States c. inability to produce edible vaccines against infectious diseases d. the ability of current transgenic varieties to pass the genetic trait on to the next generation

a

The polymerase chain reaction (PCR) requires template DNA, primers, DNA polymerase, and __________. a. a mixture of the four nucleotides A,T,C,G b. DNA ligase c. plasmid DNA d. reverse transcriptase

a

Which of the following is used to separate fragments of DNA by size? a. gel electrophoresis b. DNA splicing c. polymerase chain reaction d. DNA insertion into a plasmid

a

Genes in the human genome sequence can be identified in all of the following ways EXCEPT a. matching genome sequences to proteins. b. comparing the human genome sequence to sequences in cDNA libraries. c. identifying start and stop codons. d. searching for groups of exons.

a *This is not an approach generally used to identify functional human genes.

Which technique will allow amplification of the DNA from the crime scene, in order to provide a large enough specimen? a. gel electrophoresis b. DNA sequencing c. transgenic introduction d. polymerase chain reaction

d

A BAC library is a. a collection of human DNA fragments carried on chromosomes in human cells. b. a collection of bacterial DNA fragments carried on chromosomes in human cells. c. a collection of bacterial DNA fragments carried on chromosomes in bacterial cells. d. a collection of human DNA fragments carried on chromosomes in bacterial cells.

d *BAC stands for "bacterial artificial chromosome."

Which of these nitrogenous bases is found in DNA but not in RNA? a. cytosine b. uracil c. adenine d. thymine

d *DNA contains thymine; RNA does not.

Which of these is a difference between a DNA and an RNA molecule? a. DNA is a polymer composed of nucleotides, whereas RNA is a polymer composed of nucleic acids. b. DNA contains uracil, whereas RNA contains thymine. c. DNA contains nitrogenous bases, whereas RNA contains phosphate groups. d. DNA is double-stranded, whereas RNA is single-stranded.

d. *(With some exceptions) DNA is a double-stranded molecule and RNA is a single-stranded molecule.

In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand. a. uracil ... cytosine b. cytosine ... uracil c. guanine ... adenine d. thymine ... cytosine

d. *This is referred to as specific base pairing.

Which of the following is the MOST correct statement about restriction enzymes and recognition sites? a. EcoR1 is the name of a particular restriction enzyme that cuts at a particular recognition sequence. b. A restriction enzyme cuts sequences of DNA at specific sites. c. Restriction enzymes produce staggered cuts in the DNA. d. A restriction enzyme cuts at a recognition sequence (a place the enzyme recognizes). e. All of the listed responses are correct.

e

A technique for separating fragments of DNA or protein according to size

gel electrophoresis

explain the steps of polymerase chain reaction

1st - the two strands of a short segment of DNA are unwound by gentle heating 2nd - then the single strands of DNA are mixed with primers able to bind to one end. Nucleotides and DNA polymerase are added 3rd - As the mixture cools, the primers pairs with the ends of the template strands 4th - Nucleotides are attached in sequence, and the DNA strands replicate. the number of double-stranded DNA molecules doubles

Field of applied science that explores applications of cutting, splicing, and creating DNA

Recombinant DNA technology

Which of the following statements about recombinant DNA is NOT true? a. The cloned cells require the addition of restriction enzymes in order to reproduce. b. The plasmid allows the recombinant DNA to be propagated. c. Genes from cells with recombinant DNA can be harvested and analyzed. d. Each colony formed from the reproducing recombinant DNA cells is a clone, genetically identical to the original cell.

a *This statement is not true. Because the recombinant DNA has already been produced, a restriction enzyme is no longer required. The reproducing cells will all be genetically identical to the cell into which the recombined DNA was initially inserted.

Of the following, which is NOT a description of genetic engineering? a. Genetic engineering often involves the insertion of a gene from a eukaryotic cell into the DNA of a bacterial cell. b. Genetic engineering is the process by which human cells are induced to produce proteins that are normally found only in bacterial cells. c. Genetic engineering is a mechanism by which the DNA from one cell can be inserted into the DNA of another cell. d. Genetic engineering is the manipulation of DNA for purposes beneficial to humans.

b

In gel electrophoresis DNA molecules migrate from _____ to _____ ends of the gel. a. acidic ... basic b. negative ... positive c. long ... short d. positive ... negative

b *An electrical current is generated across the gel, and DNA molecules migrate from the negative end toward the positive end.

In the process of producing recombinant DNA using human DNA, __________ is used to connect human and plasmid DNA together. a. DNA polymerase b. DNA ligase c. a restriction enzyme d. RNA polymerase

b *DNA ligase binds fragments of DNA together after restriction enzymes have cut them.

In the second PCR step, primers bond with the single stranded DNA. This process is called ________. a. polymerization b. hybridization or annealing c. Thermus aquaticus d. thermocycling

b *Hybridization, or annealing, is the process by which a new strand is created from part of the old strand and the primers present in the environment.

What is the major difference between the strategies of map-based sequencing and shotgun sequencing? a. Shotgun sequencing was the more successful strategy in sequencing the human genome. b. In shotgun sequencing, DNA fragments are sequenced before their correct order is known. c. Shotgun sequencing was the original strategy for sequencing the human genome. d. Map-based sequencing requires the DNA to be cut into small fragments.

b *Map-based sequencing involves determining the correct order of DNA fragments before they are sequenced.

Why are chromosomes cut into fragments for sequencing? a. Shorter fragments make it easier to locate disease genes. b. A DNA sequencing reaction can only accurately determine about 500 bases of DNA. c. Shorter fragments speed up the sequencing reaction. d. The sequencing reaction itself cuts the DNA into fragments.

b *Scientists adopted a strategy called map-based sequencing, in which the DNA of a cell is cut into relatively large pieces. These large pieces are then cut into smaller fragments that can be sequenced individually and later aligned to produce the full sequence of a chromosome.

Which of the following is needed for sequencing DNA? a. gel electrophoresis b. DNA polymerase c. primers d. all of these choices

d

The technical application of biological knowledge for human purposes is called

biotechnology

A tiny amount of blood was recovered from a crime scene. What technique will enable comparison of this DNA to that of a potential suspect? a. DNA sequencing b. gene therapy c. DNA fingerprinting d. DNA cloning

c

When referring to a plasmid, it can be said that ________. a. the plasmid is found in the eukaryotic cell of interest b. a plasmid is an enzyme used in genetic engineering c. the plasmid is a circular piece of DNA found in a bacterium d. a plasmid is a mechanism by which scientists are able to incorporate bacterial DNA into eukaryotic DNA

c

Which of the following acts like a molecular copying machine, rapidly making large numbers of specific sequences of DNA? a. DNA ligase b. DNA sequencing c. polymerase chain reaction d. DNA fingerprinting

c

Which of the following describes transgenic plants? a. They are viewed with suspicion in the United States, where transgenic imports are restricted. b. They are viewed as a step toward greater biodiversity in our major crops. c. They are another method to maximize crop production. d. They are readily accepted in Europe, where the vast majority of processed food products contain genetically modified ingredients.

c

Which of the following is the correct order of events in the polymerase chain reaction (PCR)? a. elongation of the DNA strand as nucleotides are added; cooling to allow primers to attach; heating to separate double-stranded DNA b. cooling to allow primers to attach; heating to separate double-stranded DNA; elongation of DNA strand as nucleotides are added c. heating to separate double-stranded DNA; cooling to allow primers to attach; elongation of DNA strand as nucleotides are added d. heating to allow primers to attach, elongation of DNA strand as nucleotides are added, cooling to separate double-stranded DNA

c

What is DNA ligase? a. DNA ligase is the formal name for the staggered ends that occur when a DNA strand is cut by a restriction enzyme. b. DNA ligase is the final restriction enzyme in the recombinant DNA process. c. DNA ligase is an enzyme that permanently pastes DNA ends together. d. DNA ligase is a technical term for the genetic engineering process involved in the production of recombinant DNA.

c *A ligase is an enzyme that "connects" molecules. DNA ligase is the enzyme that permanently pastes together the DNA ends.

In the first PCR step, denaturation, the hydrogen bonds are broken by the ________. a. DNA polymerase b. temperature of 72∘ c. 95∘ temperature d. DNA primer

c *It is the heat that supplies the energy to break the hydrogen bonds and allows the strands to separate.

How many DNA molecules would there be after four cycles of PCR if the initial reaction mixture contained two DNA molecules? a. 8 b. 16 c. 32 d. 64

c *Thirty-two DNA molecules are produced if two molecules are doubled four times. 2x2 = 4 4x2 = 8 8x2 = 16 16x2 = 32

The function of the Taq polymerase is to ________. a. sort the single-stranded DNA molecules so that appropriate sections can be lined up b. raise the temperature to 72∘∘ and hold it there c. add complementary DNA nucleotides to the growing DNA molecule d. incubate the single strand of DNA so that the new and complete molecule is built

c The heat-stable Taq polymerase builds the new DNA molecule by adding complementary nucleotides to the single strand.

Genetically engineered human insulin, human growth hormone, and human clotting factor VIIIVIII are made by __________. a. gel electrophoresis b. polymerase chain reaction c. DNA fingerprinting d. transgenic bacteria

d

Which of the following is NOT needed in a PCR thermocycler? a. DNA nucleotides b. DNA polymerase c. DNA primer d. RNA polymerase

d

Manipulation of the genetic makeup of cells or whole organisms, including humans, is known as

genetic engineering

The planned alteration of the genetic makeup of an organism by modifying, inserting, or deleting genes or groups of genes

genetic engineering

A technique for making multiple identical copies of DNA in a test tube

polymerase chain reaction (PCR)

can be used to make millions of copies of a small fragment of DNA very quickly

polymerase chain reaction (PCR)

Both DNA and RNA are nucleic acids composed of nucleotides. true false

true