BCH 3025 exam 2- UF UPDATED ACTUAL
Exam Questions and CORRECT Answers
Double-stranded regions of RNA: - CORRECT ANSWER - Can form between two self-
complementary regions of the same single strand of RNA
Which of the following is a palindromic sequence? - CORRECT ANSWER - GGATCC
CCTAGG
The compound that consists of ribose linked by an N-glycosidic bond to N-9 of adenine is: -
CORRECT ANSWER - Adenosine
In the Watson-Crick model of DNA structure (now called B-form DNA): - CORRECT
ANSWER - The bases occupy the interior of the helix
Which of the following is not true of all naturally occurring DNA? - CORRECT
ANSWER - The ratio A+T/G+C is constant for all natural DNAs
The phosphodiester bonds that link adjacent nucleotides in both RNA and DNA: - CORRECT
ANSWER - Join the 3' hydroxyl of one nucleotide to the 5' hydroxyl of the next
In the Watson-Crick model of DNA structure: - CORRECT ANSWER - The distance
between two adjacent bases in one strand is about 3.4 Å
The difference between a ribonucleotide and a deoxyribonucleotide is: - CORRECT
ANSWER - A deoxyribonucleotide has an —H instead of an —OH at C-2
Triple-helical DNA structures can result from Hoogsteen (non Watson-Crick) interactions. These
interactions are
primarily: - CORRECT ANSWER - Hydrogen bonds involving the bases
,The phosphodiester bonds that link adjacent nucleotides in both RNA and DNA: - CORRECT
ANSWER - Join the 3' hydroxyl of one nucleotide to the 5' hydroxyl of the next
The "energy carrier" ATP is an example of a(n): - CORRECT ANSWER -
Ribonucleosidetriphosphate
In the Watson-Crick model for the DNA double helix (B form), the A-T and G-C base pairs
share which one of the
following properties? - CORRECT ANSWER - The distance between the two glycosidic
(base-sugar) bonds is the same in both base pairs, within a few
tenths of an angstro
Which one of the following is true of the pentoses found in nucleic acids? - CORRECT
ANSWER - The pentoses are always in the beta-furanose forms
A major component of RNA but not of DNA is: - CORRECT ANSWER - Uracil
For the oligoribonucleotide pACGUAC: - CORRECT ANSWER - The nucleotide at the 5'
end has a phosphate on its 5' hydroxyl
The experiment of Avery, MacLeod, and McCarty in which nonvirulent bacteria were made
virulent by
transformation was significant because it showed that: - CORRECT ANSWER - Genes are
composed of DNA only
When double-stranded DNA is heated at neutral pH, which change does not occur? - CORRECT
ANSWER - The covalent N-glycosidic bond between the base and the pentose breaks
B-form DNA in vivo is a ________-handed helix, _____ Å in diameter, with a rise of ____ Å per
base pair. - CORRECT ANSWER - Right; 20; 3.4
, In comparison with DNA-DNA double helices, the stability of DNA-RNA and RNA-RNA
helices is: - CORRECT ANSWER - RNA-RNA > DNA-RNA > DNA-DNA
In double-stranded DNA: - CORRECT ANSWER - The two strands have complementary
sequences
n nucleotides and nucleic acids, syn and anti conformations relate to: - CORRECT
ANSWER - Rotation around the sugar-base bond
The phosphodiester bond that joins adjacent nucleotides in DNA: - CORRECT
ANSWER - Associates ionically with metal ions, polyamines, and proteins
The ribonucleotide polymer (5')GTGATCAAGC(3') could only form a double-stranded structure
with: - CORRECT ANSWER - (5')GCTTGATCAC(3')
The double helix of DNA in the B-form is stabilized by: - CORRECT ANSWER -
Nonspecific base-stacking interaction between two adjacent bases in the same strand
Compounds that generate nitrous acid (such as nitrites, nitrates, and nitrosamines) change DNA
molecules by: - CORRECT ANSWER - Deamination of bases
In living cells, nucleotides and their derivatives can serve as: - CORRECT ANSWER - All
of the listed answers
Which of the following statements concerning the tautomeric forms of bases such as uracil is
correct? - CORRECT ANSWER - The lactam form predominates at neutral pH
In a double-stranded nucleic acid, cytosine typically base-pairs with: - CORRECT
ANSWER - Guanine
Exam Questions and CORRECT Answers
Double-stranded regions of RNA: - CORRECT ANSWER - Can form between two self-
complementary regions of the same single strand of RNA
Which of the following is a palindromic sequence? - CORRECT ANSWER - GGATCC
CCTAGG
The compound that consists of ribose linked by an N-glycosidic bond to N-9 of adenine is: -
CORRECT ANSWER - Adenosine
In the Watson-Crick model of DNA structure (now called B-form DNA): - CORRECT
ANSWER - The bases occupy the interior of the helix
Which of the following is not true of all naturally occurring DNA? - CORRECT
ANSWER - The ratio A+T/G+C is constant for all natural DNAs
The phosphodiester bonds that link adjacent nucleotides in both RNA and DNA: - CORRECT
ANSWER - Join the 3' hydroxyl of one nucleotide to the 5' hydroxyl of the next
In the Watson-Crick model of DNA structure: - CORRECT ANSWER - The distance
between two adjacent bases in one strand is about 3.4 Å
The difference between a ribonucleotide and a deoxyribonucleotide is: - CORRECT
ANSWER - A deoxyribonucleotide has an —H instead of an —OH at C-2
Triple-helical DNA structures can result from Hoogsteen (non Watson-Crick) interactions. These
interactions are
primarily: - CORRECT ANSWER - Hydrogen bonds involving the bases
,The phosphodiester bonds that link adjacent nucleotides in both RNA and DNA: - CORRECT
ANSWER - Join the 3' hydroxyl of one nucleotide to the 5' hydroxyl of the next
The "energy carrier" ATP is an example of a(n): - CORRECT ANSWER -
Ribonucleosidetriphosphate
In the Watson-Crick model for the DNA double helix (B form), the A-T and G-C base pairs
share which one of the
following properties? - CORRECT ANSWER - The distance between the two glycosidic
(base-sugar) bonds is the same in both base pairs, within a few
tenths of an angstro
Which one of the following is true of the pentoses found in nucleic acids? - CORRECT
ANSWER - The pentoses are always in the beta-furanose forms
A major component of RNA but not of DNA is: - CORRECT ANSWER - Uracil
For the oligoribonucleotide pACGUAC: - CORRECT ANSWER - The nucleotide at the 5'
end has a phosphate on its 5' hydroxyl
The experiment of Avery, MacLeod, and McCarty in which nonvirulent bacteria were made
virulent by
transformation was significant because it showed that: - CORRECT ANSWER - Genes are
composed of DNA only
When double-stranded DNA is heated at neutral pH, which change does not occur? - CORRECT
ANSWER - The covalent N-glycosidic bond between the base and the pentose breaks
B-form DNA in vivo is a ________-handed helix, _____ Å in diameter, with a rise of ____ Å per
base pair. - CORRECT ANSWER - Right; 20; 3.4
, In comparison with DNA-DNA double helices, the stability of DNA-RNA and RNA-RNA
helices is: - CORRECT ANSWER - RNA-RNA > DNA-RNA > DNA-DNA
In double-stranded DNA: - CORRECT ANSWER - The two strands have complementary
sequences
n nucleotides and nucleic acids, syn and anti conformations relate to: - CORRECT
ANSWER - Rotation around the sugar-base bond
The phosphodiester bond that joins adjacent nucleotides in DNA: - CORRECT
ANSWER - Associates ionically with metal ions, polyamines, and proteins
The ribonucleotide polymer (5')GTGATCAAGC(3') could only form a double-stranded structure
with: - CORRECT ANSWER - (5')GCTTGATCAC(3')
The double helix of DNA in the B-form is stabilized by: - CORRECT ANSWER -
Nonspecific base-stacking interaction between two adjacent bases in the same strand
Compounds that generate nitrous acid (such as nitrites, nitrates, and nitrosamines) change DNA
molecules by: - CORRECT ANSWER - Deamination of bases
In living cells, nucleotides and their derivatives can serve as: - CORRECT ANSWER - All
of the listed answers
Which of the following statements concerning the tautomeric forms of bases such as uracil is
correct? - CORRECT ANSWER - The lactam form predominates at neutral pH
In a double-stranded nucleic acid, cytosine typically base-pairs with: - CORRECT
ANSWER - Guanine
