chap 9

Question 1

What is the end goal of PCR?

Answer 1

To quickly increase the number of copies of a specific DNA sequence

Question 2

PCR stands for

Answer 2

polymerase chain reaction.

Question 3

an application that uses PCR?

Answer 3

Sequencing a gene, diagnosing a disease, and providing enough DNA for cloning into another organism

Question 4

function of the primers in PCR?

Answer 4

hey provide a 3’ end for the DNA polymerase.

Question 5

In which direction does DNA polymerase synthesize the new DNA strand?

Answer 5

5’ to 3’

Question 6

What provides the energy for DNA polymerization in a PCR reaction?

Answer 6

Deoxyribonucleoside triphosphates

Question 7

Why is DNA polymerase from Thermus aquaticus ideal for PCR?

Answer 7

It can withstand the high temperatures associated with PCR.

Question 8

What is the temperature used for the extension step?

Answer 8

72 °C

Question 9

How do the strands separate during PCR?

Answer 9

The high heat of the denaturation step breaks the hydrogen bonds between the two strands.

Question 10

What is a thermocycler?

Answer 10

The machine that controls the heat of the reaction, cycling between the different temperatures of the different steps during PCR

Question 11

what is the sequence of the temperatures of a typical PCR reaction?

Answer 11

94 °C, 60 °C, 72 °C

Question 12

If you used a broken thermocycler that could not heat above 75°C, which of the following problems could you expect?

Answer 12

You would not get any amplification of DNA.

The DNA strands would never separate, thus no amplification would occur.

Question 13

Which of the following provides the specificity of the PCR reaction? 
A. primers
B. Taq polymerase
C. heating to 94°C
D. separated DNA strands

Answer 13

primers

Primers bind to specific regions of the DNA and determine which area(s) will be amplified.

Question 14

A new arrow labeled “lengthens” could be added between __________.

Answer 14

“Taq polymerase” → “primers”

Question 15

How do restriction enzymes cut DNA sequences?

Answer 15

They cut DNA at sites, called recognition sites, that have specific nucleotide sequences.

Question 16

how might recombinant DNA technology be used to prevent a genetic disorder caused by a mutation in a single gene?

Answer 16

To insert a desirable gene, remove an undesirable gene, or replace a defective gene with a functioning gene

Question 17

To insert a desirable gene, remove an undesirable gene, or replace a defective gene with a functioning gene

Answer 17

DNA ligase

Question 18

Why would a recombinant (genetically engineered) DNA molecule be inserted into a host cell?

Answer 18

It can be copied, transcribed, and translated into a desired protein.

Question 19

Which statement best describes restriction enzymes?

Answer 19

Which statement best describes restriction enzymes?

Question 20

property of useful vectors?

Answer 20

• They must be able to self-replicate.
• They must be small enough to allow them to be manipulated prior to injection.
• They must have properties that allow their survival in the host cell.

Question 21

Foreign DNA can be inserted into cells using a variety of different methods. Which method involves the formation of microscopic pores in the cell’s membrane?

Answer 21

electroporation

Question 22

Why is baker’s yeast useful for expressing genetically engineered genes?

Answer 22

Yeast cells are eukaryotic and so would likely be successful in expressing eukaryotic genes.

Question 23

methods could be used to identify the source of an outbreak?

Answer 23

DNA fingerprinting

Question 24

Recombinant DNA technology is commonly used to move DNA from one type of cell to another.

Answer 24

• It allows researchers to make protein products of a gene.
• It can be used to screen individuals for many different types of genetic diseases.
• It allows researchers to make many copies of a gene of interest.

Question 25

Which of the following applications of recombinant DNA technology is NOT controversial (argument) ?

A. biological weapons development
B. genetic food modification
C. genetic screening
D. metagenomics

Answer 25

D. metagenomics=study of the structure of nucleotide sequences

Question 26

You’d like to make a fluorescent bacterium (!). the correct sequence of procedures that you would use?

Answer 26

1. Amplify the gene using PCR.
2. Insert the gene into a plasmid vector.
3. Transform the vector into the bacteria.

Question 27

foreign genes can be inserted into plant cells

Answer 27

A. Scientists have created plants that are resistant to herbicides by using a mutant enzyme gene from Salmonella.
B. Scientists have created plants that produce an insect toxin originally found in bacteria.
D. Scientists have used gene silencing to create tomatoes with a longer shelf life.

Question 28

The reaction catalyzed by reverse transcriptase is

Answer 28

mRNA → cDNA.

Question 29

Biotechnology involves the

Answer 29

use of microorganisms to make desired products, the use of animal cells to make vaccines, and the development of disease-resistanct crop plants.

Question 30

The Human Genome Project, which was completed in 2003, was focused on

Answer 30

determining the nucleotide sequence of the entire human genome.

Question 31

Self-replicating DNA used to transmit a gene from one organism to another is a

Answer 31

vector.

Question 32

In the Southern blot technique,

Answer 32

A. restriction enzyme digestion of DNA
B. electrophoresis to separate fragments
C. transfer of DNA to nitrocellulose
D. addition of a labeled probe to identify the gene of interest

Question 33

The Pap test for cervical cancer involves microscopic examination of cervical cells for cancerous cells. A new, rapid diagnostic test to detect human papilloma virus (HPV) DNA before cancer develops is done without microscopic exam. The steps involved in this FastHPV test are listed below. What is the second step?
A. add enzyme substrate.
B. Add enzyme-linked antibodies against DNA-RNA.
C. Lyse human cells.
D. Add an RNA probe for HPV DNA.
E. The order is unimportant.

Answer 33

Add an RNA probe for HPV DNA.