Genetics Exam Test Questions and
answers graded A+
The size of the human genome is approximately: - ANS✅✅3 billion base pairs
The model for semiconservative DNA replication was first suggested/proposed by: -
ANS✅✅Watson and Crick
Who's experiment first PROVED the semiconservative DNA replication model? - ANS✅✅Messelson
and Stahl
Which one of the following statements about DNA polymerase III of E. coli is not true?
a) It synthesizes new DNA by adding to the 3' end of the growing chain
b) It requires a primer
c) it possesses a 5' exonuclease activity
d) It possesses a 3' exonucelase activity
e) It synthesizes the majority of the new DNA during chromosome replication - ANS✅✅C) It
possesses a 5' exonuclease activity
-nick repair is done by DNA Pol I
Which of the following enzymes is considered a topoisomerase?
a) DNA Pol I
b) helicase
c) primase
d) DNA gyrase
e) DNA ligase - ANS✅✅D) DNA gyrase
What are enzymes that regulate the overwinding or underwinding of DNA? -
ANS✅✅Topoisomerases
Which E. coli enzyme removes the primers used in DNA synthesis (5' exonuclease activity)? -
ANS✅✅DNA Polymerase I
,One strand of the DNA duplex is synthesized in a continuous fashion. The other is synthesized as a
series of relatively short fragments. This discontinuous method of DNA replication was first
suggested by: - ANS✅✅Reiji and Tuneko Okazaki
What is the region of the E. coli cell where the chromosome is found called? - ANS✅✅nucleoid
Studies of the polytene chromosomes found in dipteran salivary gland cells revealed that
chromosome puffs were found: - ANS✅✅in regions of high gene expression activity
A DNA molecule is found to have MORE than 10.4 base pairs per turn of the helix. It would be best
described as being: - ANS✅✅negatively supercoiled
A DNA molecule is found to have LESS than 10.4 base pairs per turn of the helix. It would be best
described as being: - ANS✅✅positively supercoiled
What is a DNA strand that codes for two alleles called? - ANS✅✅heteroduplex
Which histone is not part of the core particle octamer found in eukaryotic chromatin? - ANS✅✅H1
(entry and exit to core particle)
Which histones are core particles that form tetramers/octamers found in eukaryotic cells? -
ANS✅✅H2A
H2B
H3
H4
In the context of eukaryotic chromatin, the 11 nm fiber is: - ANS✅✅A string of nucleosomes (nm)
In the context of eukaryotic chromatin, the 2 nm fiber is: - ANS✅✅The DNA double helix
In the context of eukaryotic chromatin, the 30 nm fiber is: - ANS✅✅a coil of nucleosomes with
about 6 per turn
, In the context of eukaryotic chromatin, the 300 nm fiber is: - ANS✅✅a repeatedly folded fiber
The 3' exonuclease activity of E. coli DNA polymerase I is very important in that it allows the enzyme
to: - ANS✅✅proofread
The 5' exonuclease activity of E. coli DNA polymerase I is very important in that it allows the enzyme
to: - ANS✅✅Carry out nick translation during DNA repair
An example of a gene or genes commonly present in genomes at more than one copy per haploid
equivalent would be: - ANS✅✅rRNA genes
Today's DNA profiling technology relies upon loci called: - ANS✅✅STRs (Short Tandem Repeats)
(microsatellites)
The synthesis of an RNA transcript from a DNA template is called: - ANS✅✅transcription
Which of the following is NOT an accepted property of the genetic code?
a) It is virtually universal
b) It is nonoverlapping
c) It is triplet
d) It is degenerate
e) UAA is used for a start signal - ANS✅✅e) it is actually AUG that is used as a start signal
UAG/UAA is the stop signal
The are six different codons that call for arginine. For this reason the genetic code is said to be: -
ANS✅✅degenerate
Histones as a group have a characteristically high content of: - ANS✅✅Lysine and arginine (20-
30%)
The triplet binding assay utilized to verify 50 of the 64 possible codons in the genetic code was
developed by: - ANS✅✅Nirenberg and Leder
answers graded A+
The size of the human genome is approximately: - ANS✅✅3 billion base pairs
The model for semiconservative DNA replication was first suggested/proposed by: -
ANS✅✅Watson and Crick
Who's experiment first PROVED the semiconservative DNA replication model? - ANS✅✅Messelson
and Stahl
Which one of the following statements about DNA polymerase III of E. coli is not true?
a) It synthesizes new DNA by adding to the 3' end of the growing chain
b) It requires a primer
c) it possesses a 5' exonuclease activity
d) It possesses a 3' exonucelase activity
e) It synthesizes the majority of the new DNA during chromosome replication - ANS✅✅C) It
possesses a 5' exonuclease activity
-nick repair is done by DNA Pol I
Which of the following enzymes is considered a topoisomerase?
a) DNA Pol I
b) helicase
c) primase
d) DNA gyrase
e) DNA ligase - ANS✅✅D) DNA gyrase
What are enzymes that regulate the overwinding or underwinding of DNA? -
ANS✅✅Topoisomerases
Which E. coli enzyme removes the primers used in DNA synthesis (5' exonuclease activity)? -
ANS✅✅DNA Polymerase I
,One strand of the DNA duplex is synthesized in a continuous fashion. The other is synthesized as a
series of relatively short fragments. This discontinuous method of DNA replication was first
suggested by: - ANS✅✅Reiji and Tuneko Okazaki
What is the region of the E. coli cell where the chromosome is found called? - ANS✅✅nucleoid
Studies of the polytene chromosomes found in dipteran salivary gland cells revealed that
chromosome puffs were found: - ANS✅✅in regions of high gene expression activity
A DNA molecule is found to have MORE than 10.4 base pairs per turn of the helix. It would be best
described as being: - ANS✅✅negatively supercoiled
A DNA molecule is found to have LESS than 10.4 base pairs per turn of the helix. It would be best
described as being: - ANS✅✅positively supercoiled
What is a DNA strand that codes for two alleles called? - ANS✅✅heteroduplex
Which histone is not part of the core particle octamer found in eukaryotic chromatin? - ANS✅✅H1
(entry and exit to core particle)
Which histones are core particles that form tetramers/octamers found in eukaryotic cells? -
ANS✅✅H2A
H2B
H3
H4
In the context of eukaryotic chromatin, the 11 nm fiber is: - ANS✅✅A string of nucleosomes (nm)
In the context of eukaryotic chromatin, the 2 nm fiber is: - ANS✅✅The DNA double helix
In the context of eukaryotic chromatin, the 30 nm fiber is: - ANS✅✅a coil of nucleosomes with
about 6 per turn
, In the context of eukaryotic chromatin, the 300 nm fiber is: - ANS✅✅a repeatedly folded fiber
The 3' exonuclease activity of E. coli DNA polymerase I is very important in that it allows the enzyme
to: - ANS✅✅proofread
The 5' exonuclease activity of E. coli DNA polymerase I is very important in that it allows the enzyme
to: - ANS✅✅Carry out nick translation during DNA repair
An example of a gene or genes commonly present in genomes at more than one copy per haploid
equivalent would be: - ANS✅✅rRNA genes
Today's DNA profiling technology relies upon loci called: - ANS✅✅STRs (Short Tandem Repeats)
(microsatellites)
The synthesis of an RNA transcript from a DNA template is called: - ANS✅✅transcription
Which of the following is NOT an accepted property of the genetic code?
a) It is virtually universal
b) It is nonoverlapping
c) It is triplet
d) It is degenerate
e) UAA is used for a start signal - ANS✅✅e) it is actually AUG that is used as a start signal
UAG/UAA is the stop signal
The are six different codons that call for arginine. For this reason the genetic code is said to be: -
ANS✅✅degenerate
Histones as a group have a characteristically high content of: - ANS✅✅Lysine and arginine (20-
30%)
The triplet binding assay utilized to verify 50 of the 64 possible codons in the genetic code was
developed by: - ANS✅✅Nirenberg and Leder
