BS 161 FINAL EXAM UPDATED ACTUAL
Questions and CORRECT Answers
In a single molecule of water, two hydrogen atoms are bonded to a single oxygen atom by -
CORRECT ANSWER - polar covalent bonds
The negative logarithmic of the hydrogen ion concentration in the solution is referred to as -
CORRECT ANSWER - pH
When are atoms most stable? - CORRECT ANSWER - when all of the electron orbitals in
the valance shell are filled
The structural formula for a certain molecule includes a group symbolized -O. The dash next to
the oxygen atom means that a single bond exists to another atom, such as a carbon. Based on the
valence of oxygen and the number of bonds it normally forms, what is the charge on the oxygen
atom in this case? - CORRECT ANSWER -
Two carbon atoms joined to each other by sharing of two pairs of electrons form a(n): -
CORRECT ANSWER - ionic bond
Plants transport water to their leaves through the xylem when water evaporates from the leaves.
The evaporating water pulls other water molecules up the xylem through - CORRECT
ANSWER -
Membrane lipids contain long chains of H-C-H groups joined by C-C bonds. Which interaction
is most likely to occurring between lipids in the membrane? - CORRECT ANSWER - van
der waals
Consider the following electronegativity values: Boron=1.8; Carbon=2.5; Chlorine=3.2;
Selenium= 2.6. Which bond is the most polar? - CORRECT ANSWER - B-Cl
,Which of the following best summarizes the relationship between dehydration reactions and
hydrolysis? - CORRECT ANSWER - Dehydration reactions assemble polymers, and
hydrolysis reactions break down polymers.
Which of the following polymers contain(s) nitrogen? - CORRECT ANSWER - Chitin
The molecular formula for glucose is C6H12O6. What would be the molecular formula for a
molecule made by linking three glucose molecules together by dehydration reactions? -
CORRECT ANSWER - C18H32O16
It became apparent to Watson and Crick after completion of their model that the DNA molecule
could carry a vast amount of hereditary information in which of the following? - CORRECT
ANSWER - Sequence of bases
What is meant by the description "antiparallel" regarding the strands that make up DNA? -
CORRECT ANSWER - The 5' to 3' direction of one strand runs counter to the 5' to 3'
direction of the other strand
If you made a change in the promoter sequence in the DNA that inactivates the promoter, what
would happen at the RNA level? - CORRECT ANSWER - The RNA polymerase would
not be able to recognize and bind the DNA, so no RNA would be made
The genetic code is essentially the same for all organisms. From this, one can logically assume
which of the following? - CORRECT ANSWER - A gene from an organism can
theoretically be expressed by any other organism
Imagine you have discovered a new species of bacteria. To begin your investigation of this
organism, you run an assay on the total nucleotide content of the bacterial DNA. If the cytosine
content of DNA from the bacterial cells is 40%, what is the adenine content? - CORRECT
ANSWER - 10%
, Which of the following does not occur in prokaryotic eukaryotic gene expression, but does in
eukaryotic gene expression? - CORRECT ANSWER - a Poly-A tail is added to the 3' end
of an mRNA and a cap is added to the 5' end
The Dystrophin gene is 2.3 million nucleotides long, however it only uses ~12,00 nucleotides to
make a protein consisting of 3,685 amino acids. This is best explained by the fact that -
CORRECT ANSWER -
Accuracy in the translation of mRNA into the primary structure of a polypeptide depends on
specificity in the: - CORRECT ANSWER - Bonding of the anticodon to the codon and the
attachment of amino acids to tRNAs
Streptomycin is an antibiotic that interferes with the function of the large subunit of the
prokaryotic ribosome. What is the consequence of treating bacteria with streptomycin. -
CORRECT ANSWER - impaired protein synthesis
DNA template strand 5'-------------3'
DNA complementary strand 3'----------5'
Given the locally unwound double strand above, in which direction does the RNA polymerase
move? - CORRECT ANSWER - 3' --> 5' along the template strand
In the transcription event of the previous DNA, where would the promoter be located? -
CORRECT ANSWER - To the right of the template strand
What enzyme catalyzes the attachment of an amino acid to tRNA? - CORRECT
ANSWER - aminoacyl-tRNA synthetase
Osmosis occurs as water can cross the lipid bilayer through specialized channels for water
movement called ________. - CORRECT ANSWER - aquaporins
Long saturated fatty acid tails _______ lipid mobility and _________ membrane fluidity. -
CORRECT ANSWER - reduce, decrease
Questions and CORRECT Answers
In a single molecule of water, two hydrogen atoms are bonded to a single oxygen atom by -
CORRECT ANSWER - polar covalent bonds
The negative logarithmic of the hydrogen ion concentration in the solution is referred to as -
CORRECT ANSWER - pH
When are atoms most stable? - CORRECT ANSWER - when all of the electron orbitals in
the valance shell are filled
The structural formula for a certain molecule includes a group symbolized -O. The dash next to
the oxygen atom means that a single bond exists to another atom, such as a carbon. Based on the
valence of oxygen and the number of bonds it normally forms, what is the charge on the oxygen
atom in this case? - CORRECT ANSWER -
Two carbon atoms joined to each other by sharing of two pairs of electrons form a(n): -
CORRECT ANSWER - ionic bond
Plants transport water to their leaves through the xylem when water evaporates from the leaves.
The evaporating water pulls other water molecules up the xylem through - CORRECT
ANSWER -
Membrane lipids contain long chains of H-C-H groups joined by C-C bonds. Which interaction
is most likely to occurring between lipids in the membrane? - CORRECT ANSWER - van
der waals
Consider the following electronegativity values: Boron=1.8; Carbon=2.5; Chlorine=3.2;
Selenium= 2.6. Which bond is the most polar? - CORRECT ANSWER - B-Cl
,Which of the following best summarizes the relationship between dehydration reactions and
hydrolysis? - CORRECT ANSWER - Dehydration reactions assemble polymers, and
hydrolysis reactions break down polymers.
Which of the following polymers contain(s) nitrogen? - CORRECT ANSWER - Chitin
The molecular formula for glucose is C6H12O6. What would be the molecular formula for a
molecule made by linking three glucose molecules together by dehydration reactions? -
CORRECT ANSWER - C18H32O16
It became apparent to Watson and Crick after completion of their model that the DNA molecule
could carry a vast amount of hereditary information in which of the following? - CORRECT
ANSWER - Sequence of bases
What is meant by the description "antiparallel" regarding the strands that make up DNA? -
CORRECT ANSWER - The 5' to 3' direction of one strand runs counter to the 5' to 3'
direction of the other strand
If you made a change in the promoter sequence in the DNA that inactivates the promoter, what
would happen at the RNA level? - CORRECT ANSWER - The RNA polymerase would
not be able to recognize and bind the DNA, so no RNA would be made
The genetic code is essentially the same for all organisms. From this, one can logically assume
which of the following? - CORRECT ANSWER - A gene from an organism can
theoretically be expressed by any other organism
Imagine you have discovered a new species of bacteria. To begin your investigation of this
organism, you run an assay on the total nucleotide content of the bacterial DNA. If the cytosine
content of DNA from the bacterial cells is 40%, what is the adenine content? - CORRECT
ANSWER - 10%
, Which of the following does not occur in prokaryotic eukaryotic gene expression, but does in
eukaryotic gene expression? - CORRECT ANSWER - a Poly-A tail is added to the 3' end
of an mRNA and a cap is added to the 5' end
The Dystrophin gene is 2.3 million nucleotides long, however it only uses ~12,00 nucleotides to
make a protein consisting of 3,685 amino acids. This is best explained by the fact that -
CORRECT ANSWER -
Accuracy in the translation of mRNA into the primary structure of a polypeptide depends on
specificity in the: - CORRECT ANSWER - Bonding of the anticodon to the codon and the
attachment of amino acids to tRNAs
Streptomycin is an antibiotic that interferes with the function of the large subunit of the
prokaryotic ribosome. What is the consequence of treating bacteria with streptomycin. -
CORRECT ANSWER - impaired protein synthesis
DNA template strand 5'-------------3'
DNA complementary strand 3'----------5'
Given the locally unwound double strand above, in which direction does the RNA polymerase
move? - CORRECT ANSWER - 3' --> 5' along the template strand
In the transcription event of the previous DNA, where would the promoter be located? -
CORRECT ANSWER - To the right of the template strand
What enzyme catalyzes the attachment of an amino acid to tRNA? - CORRECT
ANSWER - aminoacyl-tRNA synthetase
Osmosis occurs as water can cross the lipid bilayer through specialized channels for water
movement called ________. - CORRECT ANSWER - aquaporins
Long saturated fatty acid tails _______ lipid mobility and _________ membrane fluidity. -
CORRECT ANSWER - reduce, decrease
