bio topic 7

Question 1

Which are two proteins that assist in the unwinding and separation of DNA strands during replication?

Answer 1

Single-strand binding protein and DNA gyrase

Question 2

What is the difference between the DNA of adult identical (monozygotic) twins?

Answer 2

Methylation pattern

Question 3

What are Okazaki fragments?

Answer 3

Small sections of DNA that are formed during discontinuous synthesis of the lagging strand during DNA replication. They are important because they allow for both daughter strands to be synthesized, which are necessary for cell division

Question 4

Current understanding of DNA is an example of the accumulated discoveries of many scientists. Which scientists are credited with establishing that DNA is the genetic material?

Answer 4

Hershey and Chase

Question 5

What does eukaryotic DNA have that is missing from prokaryotic DNA?

Answer 5

Introns

Question 6

What stays from pre-mature mRNA for the mature mRNA?

Answer 6

Only exons

Question 7

What is the reason for the use of dideoxyribonucleotides to terminate sequences in base sequencing?

Answer 7

Nucleotides cannot form 5′ to 3′ linkages with dideoxyribonucleotides.

Question 8

What applies to DNA base sequences?

Answer 8

Promoters are transcribed along with the gene

Question 9

In transcription, which enzyme has a role similar to that of helicase in replication?

Answer 9

RNA polymerase

Question 10

What is a function of DNA polymerase I?

Answer 10

Removes RNA primer and replaces it with DNA

Question 11

Which regions of DNA code for the production of specific proteins?

Answer 11

Exons

Question 12

What are Okazaki fragments?

Answer 12

Short sections of DNA formed during DNA replication

Question 13

What does nucleosome consist of?

Answer 13

DNA and histones

Question 14

What is a nucleosome?

Answer 14

A DNA molecule wrapped around histone proteins

Question 15

What is the reason for Okazaki fragments being formed during DNA replication?

Answer 15

To enable replication of the 3′ → 5′ (lagging) strand

Question 16

What happens during the formation of Okazaki fragments?

Answer 16

DNA polymerase III adds nucleotides in the 5′→ 3′ direction

Question 17

After which process are introns removed?

Answer 17

Translation

Question 18

Which structure found in eukaryotes has a single membrane?

Answer 18

Lysosome

Question 19

What happens to an RNA molecule in eukaryotes after transcription in order to process it into mRNA?

Answer 19

Adenine nucleotides are added at the 3’ end

Question 20

Which of these events occurs first in translation?

Answer 20

Small ribosomal subunits binds to mRNA

Question 21

During modification in eukaryotes, mRNA is spliced. What is splicing of mRNA?

Answer 21

Linking together exons

Question 22

Some regions of DNA do not code for the production of proteins. What are these regions of DNA used as?

Answer 22

Telomeres are coding for production of tRNA

Question 23

In which process(es) do nucleosomes play a role in eukaryotes?

Answer 23

Transcription regulation and DNA supercoiling

Question 24

What is a feature of transcription?

Answer 24

RNA polymerase binds to the promoter region.

Question 25

What happens during transcription in eukaryotes?

Answer 25

RNA polymerase separates DNA strands.

Question 26

What makes up eukaryotic RNA immediately after transcription?

Answer 26

Exons and introns

Question 27

What strand is a template for an mRNA single strand sequence?

Answer 27

An antisense strand, as through RNA polymerase the RNA strand is made of the sense strand

Question 28

The sequence of nucleotides in a section of RNA is: GCCAUACGAUCG What is the base sequence of the DNA sense strand?

Answer 28

GCCATACGATCG

Question 29

The antisense strand on the DNA molecule coding for three codons of a gene is TATCGCACG What are the anticodons of the three tRNA molecules that correspond to this sequence?

Answer 29

UAU, CGC and ACG

Question 30

What is the primary function of the free ribosomes shown in the electron micrograph?

Answer 30

Synthesize proteins to be used within the cell

Question 31

Which types of interactions are found in a part of a protein with secondary but not tertiary structure?

Answer 31

Hydrogen bonds

Question 32

What are polysomes?

Answer 32

Aggregates of numerous ribosomes that are in the process of actively translating mRNA into protein

Question 33

What are polysomes?

Answer 33

Many ribosomes joined to one mRNA

Question 34

R group interactions that contribute to...

Answer 34

...tertiary structure include hydrogen bonding, ionic bonding, dipole-dipole interactions, and London dispersion forces – basically, the whole gamut of non-covalent bonds.

Question 35

How do R group interactions contribute to protein structure?

Answer 35

Stabilizing further foldings of a polypeptide into a tertiary structure

Question 36

What can attach to the end of an tRNA

Answer 36

An amino acid

Question 37

Which types of interactions are found in a part of a protein with secondary but not tertiary structure?

Answer 37

Hydrogen bonds

Question 38

What does post-transcriptional modification of eukaryotic mRNA include? I. Introns are removed from mRNA. II. Exons are joined together to form mature mRNA. III. A 5′ cap and 3′ poly-A tail are added to mRNA.

Answer 38

All three

Question 39

What determines the primary structure of hemoglobin?

Answer 39

Genetic information

Question 40

Which best describes the tertiary structure of a protein?

Answer 40

The structure formed from interactions between the amino acid side groups

Question 41

Which cell component synthesizes actin and myosin?

Answer 41

Free ribosomes

Question 42

What is the distinction between highly repetitive DNA sequences and single-copy genes?

Answer 42

The highly repetitive sequences are not replicated