Exam 4

Front 1

If DNA of a particular species was analyzed and it was found that it contains 27 percent A, what would be the percentage of C?

Back 1

23 Percent

Front 2

The experiments by Hershey and Chase helped confirm that DNA was the hereditary material on the basis of the finding that:

Back 2

radioactive phosphorus was found in the cell

Front 3

DNA double helix does not have...

Back 3

Uracil

Front 4

In eukaryotes, what is the DNA wrapped around?

Back 4

histones

Front 5

Meselson and Stahl's experiments proved that DNA replicates by which mode?

Back 5

semi-conservative

Front 6

If the sequence of the 5'-3' strand is AATGCTAC, then the complementary sequence has the following sequence:

Back 6

3'-TTACGATG-5'

Front 7

what is not involved during the formation of the replication fork?

Back 7

ligase

Front 8

Which of the following does the enzyme primase synthesize?

Back 8

RNA primer

Front 9

Meselson and Stahl's experiments proved that DNA replicates by which mode?

Back 9

semi-conservative

Front 10

How did the scientific community learn that DNA replication takes place in a semi-conservative fashion?

Back 10

Meselson’s experiments with E. coli grown in 15N deduced this finding.

Front 11

Which of the following components is not involved during the formation of the replication fork?

Back 11

ligase

Front 12

Which of the following does the enzyme primase synthesize?

Back 12

RNA Primer

Front 13

In which direction does DNA replication take place?

Back 13

5'-3'

Front 14

The ends of the linear chromosomes are maintained by

Back 14

telomerase

Front 15

During proofreading, which of the following enzymes reads the DNA?

Back 15

DNA Pol

Front 16

The initial mechanism for repairing nucleotide errors in DNA is ________.

Back 16

DNA polymerase proofreading

Front 17

The AUC and AUA codons in mRNA both specify isoleucine. What feature of the genetic code explains this?

Back 17

degeneracy

Front 18

The -10 and -35 regions of prokaryotic promoters are called consensus sequences because ________.

Back 18

they are similar in all bacterial species

Front 19

Which feature of promoters can be found in both prokaryotes and eukaryotes?

Back 19

TATA Box

Front 20

What transcripts will be most affected by low levels of α-amanitin?

Back 20

pre-mRNAs

Front 21

Which pre-mRNA processing step is important for initiating translation?

Back 21

7-methylguanosine cap

Front 22

What processing step enhances the stability of pre-tRNAs and pre-rRNAs?

Back 22

methylation

Front 23

The RNA components of ribosomes are synthesized in the ________

Back 23

nucleolus

Front 24

In any given species, there are at least how many types of aminoacyl tRNA synthetases?

Back 24

20

Front 25

Control of gene expression in eukaryotic cells occurs at which level(s)?

Back 25

epigenetic, transcriptional, post-transcriptional, translational, and post-translational levels

Front 26

Post-translational control refers to:

Back 26

regulation of gene expression after translation

Front 27

If glucose is absent, but so is lactose, the lac operon will be ________.activated

Back 27

repressed

Front 28

Prokaryotic cells lack a nucleus. Therefore, the genes in prokaryotic cells are:

Back 28

transcribed and translated almost simultaneously and

transcriptionally controlled because translation begins before transcription ends

Front 29

What are epigenetic modifications?

Back 29

the addition of reversible changes to histone proteins and DNA

Front 30

Which of the following are true of epigenetic changes?

Back 30

allow DNA to be transcribed

move histones to open or close a chromosomal region

are temporary

Front 31

The binding of ________ is required for transcription to start.

Back 31

RNA polymerase

Front 32

What will result from the binding of a transcription factor to an enhancer region?

Back 32

increased transcription of a distant gene

Front 33

Which of the following are involved in post-transcriptional control?

Back 33

control of RNA splicing

control of RNA shuttling

control of RNA stability

Front 34

Binding of an RNA binding protein will ________ the stability of the RNA molecule.

Back 34

either increase or decrease

Front 35

Post-translational modifications of proteins can affect which of the following?

Back 35

protein function

Front 36

Cancer causing genes are called ________.

Back 36

oncogenes

Front 37

GMOs are created by ________.

Back 37

introducing recombinant DNA into an organism by any means

Front 38

Gene therapy can be used to introduce foreign DNA into cells ________.

Back 38

of tissues to cure inheritable disease

Front 39

Insulin produced by molecular cloning:

Back 39

is a recombinant protein

Front 40

Bt toxin is considered to be ________.

Back 40

an organic insecticide produced by bacteria

Front 41

ESTs are ________.

Back 41

generated after a cDNA library is made

unique sequences in the genome

useful for mapping using sequence information

Front 42

Linkage analysis ________.

Back 42

is based on the natural recombination process

Front 43

Genetic recombination occurs by which process?

Back 43

crossing over

Front 44

Individual genetic maps in a given species are

Back 44

genetically similar

Front 45

Information obtained by microscopic analysis of stained chromosomes is used in:

Back 45

cytogenetic mapping

Front 46

The chain termination method of sequencing:

Back 46

uses labeled ddNTPs

Front 47

Whole-genome sequencing can be used for advances in:

Back 47

the medical field

agroculture

biomechanics

Front 48

Sequencing an individual person’s genome

Back 48

is currently possible

could lead to legal issues regarding discrimination and privacy

could help make informed choices about medical treatment

Front 49

What is the most challenging issue facing genome sequencing?

Back 49

the ethics of using information from genomes at the individual level

Front 50

Which statement is true?

Back 50

Viruses are acellular.

Front 51

The viral ________ plays a role in attaching a virion to the host cell.

Back 51

Capsid

envelope

Front 52

Viruses_______.

Back 52

vary in shape

Front 53

Which statement is not true of viral replication?

Back 53

Newly released virions can infect adjacent cells.

Front 54

Which statement is true of viral replication?

Back 54

During attachment, the virus attaches at specific sites on the cell surface.

Front 55

Which statement is true of reverse transcriptase?

Back 55

It transcribes RNA to make DNA.

Front 56

Oncogenic virus cores can be_____

Back 56

either RNA or DNA

Front 57

Which of the following is NOT used to treat active viral disease?

Back 57

antiobiotics

Front 58

Vaccines_______.

Back 58

kill viruses

Front 59

Which of the following is not associated with prions?

Back 59

DNA

Front 60

helicase

Back 60

during replication, this enzyme helps to open up the DNA helix by breaking the hydrogen bonds

Front 61

lagging strand

Back 61

during replication, the strand that is replicated in short fragments and away from the replication fork

Front 62

leading strand

Back 62

strand that is synthesized continuously in the 5'-3' direction which is synthesized in the direction of the replication fork

Front 63

ligase

Back 63

enzyme that catalyzes the formation of a phosphodiester linkage between the 3' OH and 5' phosphate ends of the DNA

Front 64

Okazaki fragment

Back 64

DNA fragment that is synthesized in short stretches on the lagging strand

Front 65

primase

Back 65

enzyme that synthesizes the RNA primer; the primer is needed for DNA pol to start synthesis of a new DNA strand

Front 66

primer

Back 66

short stretch of nucleotides that is required to initiate replication; in the case of replication, the primer has RNA nucleotides

Front 67

topoisomerase

Back 67

enzyme that causes underwinding or overwinding of DNA when DNA replication is taking place