Molecular Biology Final Exam Study Guide
UPDATED Questions and CORRECT
Answers
If a DNA fragment contains 210 base pairs, which of the following is true?
a. The DNA length is about 99A
b. The DNA fragment has about 420 H bonds
c. The diameter of the DNA helix is 22A
d. The DNA fragment has about 20 helix turns - CORRECT ANSWER - d. The DNA
fragment has about 20 helix turns
In a piece of DNA, which of the following is true?
a. The ratio of A, T, C, and G is equal
b. The ratio of T must be different from C
c. The ratio of G is always equal to C
d. All of the above are true - CORRECT ANSWER - c. The ratio of G is always equal to C
Which of the following statements is false?
a. The two strands of a DNA helix are identical in base number
b. The two strands of a DNA helix are identical in length
c. The two strands of a DNA helix are identical in hydrogen bond numbers
d. The two strands of a DNA helix are identical in direction - CORRECT ANSWER - d.
The two strands of a DNA helix are identical in direction
The following proportions exist in DNA: C+A = T+G
a. Yes, this is always true for regular DNA molecules
b. Nope, its actually A=G, C=T
c. Untrue, you lying varmint! C>G, A>T
,d. None of the above - CORRECT ANSWER - a. Yes, this is always true for regular DNA
molecules
The minor groove of a DNA double helix
a. Presents a wide variety of chemical groups to other proteins
b. Is not much different from the major groove
c. Is distinctive in prokaryotes but not in eukaryotes
d. Is the site of histone/DNA interactions - CORRECT ANSWER - d. Is the site of
histone/DNA interactions
In a nucleotide, such as dATP the phosphate is attached to the ___ carbon of deoxyribose
a. 5'
b. 3'
c. 2'
d. 1' - CORRECT ANSWER - a. 5'
The chemical bond that links the nucleotides one by one in a single DNA string is
a. H bond
b. Peptide bond
c. Phosphodiester bond 5' with 3' phosphate
d. Phosphodiester bond 3' with 5' phosphate - CORRECT ANSWER - c. Phosphodiester
bond 5' with 3' phosphate
Core histones
a. Contain n-terminal tails that can be chemically modified
b. Are small and rich in R and L
c. Are very similar in amino acid sequence among different organisms from humans to plants
d. All - CORRECT ANSWER - c. Are very similar in amino acid sequence among
different organisms from humans to plants
,The histones are
a. Highly conserved that they are identical among all organisms
b. All over 50 kDa in size
c. Highly conserved that there are only a few amino acid differences between plants and humans
d. Composed of different aa in addition to the 20 common aa - CORRECT ANSWER - c.
Highly conserved that there are only a few amino acid differences between plants and humans
Which of the following is true?
a. DNA is usually in A form
b. DNA is usually in the B form
c. DNA is usually in the Z form
d. DNA can take any of the three forms in the cell - CORRECT ANSWER - b. DNA is
usually in the B form
DNA denature and re-nature (annealing) is not important for
a. Southern blot
b. Northern blot
c. Western blot
d. All of the above - CORRECT ANSWER - c. Western blot
When DNA fragments with identical sequence form different helices, which of the follow is
true?
a. The A form is the longest
b. The Z form is a right handed helix
c. The A form is thicker than the B form
d. The B form is thicker than the A form - CORRECT ANSWER - c. The A form is thicker
than the B form
, Which of the following statements is false?
a. RNA has U
b. RNA has ribose
c. RNA has more diversified secondary structure
d. RNA cannot form double helix structure at all - CORRECT ANSWER - d. RNA cannot
form double helix structure at all
Which of the following characteristics of RNA does not contribute to RNA's unique feature?
a. RNA contains U instead of T
b. RNA has an extra -OH group
c. RNA can allow triple base pairing
d. RNA contains phosphate group - CORRECT ANSWER - d. RNA contains phosphate
group
The H2A and H2B
a. Bind with linker DNA
b. Form tetramers
c. Form dimers
d. Are the same protein in two different forms - CORRECT ANSWER - c. Form dimers
The DNA fragment wrapping around the histone core of a nucleosome
a. Is about 50 bp
b. Is about 147 bp
c. Varies in length in different cells
d. Varies in length substantially among different species - CORRECT ANSWER - b. Is
about 147 bp
Which of the following is false?
a. The number of H2A and H2B are always the same in regular nucleosome
UPDATED Questions and CORRECT
Answers
If a DNA fragment contains 210 base pairs, which of the following is true?
a. The DNA length is about 99A
b. The DNA fragment has about 420 H bonds
c. The diameter of the DNA helix is 22A
d. The DNA fragment has about 20 helix turns - CORRECT ANSWER - d. The DNA
fragment has about 20 helix turns
In a piece of DNA, which of the following is true?
a. The ratio of A, T, C, and G is equal
b. The ratio of T must be different from C
c. The ratio of G is always equal to C
d. All of the above are true - CORRECT ANSWER - c. The ratio of G is always equal to C
Which of the following statements is false?
a. The two strands of a DNA helix are identical in base number
b. The two strands of a DNA helix are identical in length
c. The two strands of a DNA helix are identical in hydrogen bond numbers
d. The two strands of a DNA helix are identical in direction - CORRECT ANSWER - d.
The two strands of a DNA helix are identical in direction
The following proportions exist in DNA: C+A = T+G
a. Yes, this is always true for regular DNA molecules
b. Nope, its actually A=G, C=T
c. Untrue, you lying varmint! C>G, A>T
,d. None of the above - CORRECT ANSWER - a. Yes, this is always true for regular DNA
molecules
The minor groove of a DNA double helix
a. Presents a wide variety of chemical groups to other proteins
b. Is not much different from the major groove
c. Is distinctive in prokaryotes but not in eukaryotes
d. Is the site of histone/DNA interactions - CORRECT ANSWER - d. Is the site of
histone/DNA interactions
In a nucleotide, such as dATP the phosphate is attached to the ___ carbon of deoxyribose
a. 5'
b. 3'
c. 2'
d. 1' - CORRECT ANSWER - a. 5'
The chemical bond that links the nucleotides one by one in a single DNA string is
a. H bond
b. Peptide bond
c. Phosphodiester bond 5' with 3' phosphate
d. Phosphodiester bond 3' with 5' phosphate - CORRECT ANSWER - c. Phosphodiester
bond 5' with 3' phosphate
Core histones
a. Contain n-terminal tails that can be chemically modified
b. Are small and rich in R and L
c. Are very similar in amino acid sequence among different organisms from humans to plants
d. All - CORRECT ANSWER - c. Are very similar in amino acid sequence among
different organisms from humans to plants
,The histones are
a. Highly conserved that they are identical among all organisms
b. All over 50 kDa in size
c. Highly conserved that there are only a few amino acid differences between plants and humans
d. Composed of different aa in addition to the 20 common aa - CORRECT ANSWER - c.
Highly conserved that there are only a few amino acid differences between plants and humans
Which of the following is true?
a. DNA is usually in A form
b. DNA is usually in the B form
c. DNA is usually in the Z form
d. DNA can take any of the three forms in the cell - CORRECT ANSWER - b. DNA is
usually in the B form
DNA denature and re-nature (annealing) is not important for
a. Southern blot
b. Northern blot
c. Western blot
d. All of the above - CORRECT ANSWER - c. Western blot
When DNA fragments with identical sequence form different helices, which of the follow is
true?
a. The A form is the longest
b. The Z form is a right handed helix
c. The A form is thicker than the B form
d. The B form is thicker than the A form - CORRECT ANSWER - c. The A form is thicker
than the B form
, Which of the following statements is false?
a. RNA has U
b. RNA has ribose
c. RNA has more diversified secondary structure
d. RNA cannot form double helix structure at all - CORRECT ANSWER - d. RNA cannot
form double helix structure at all
Which of the following characteristics of RNA does not contribute to RNA's unique feature?
a. RNA contains U instead of T
b. RNA has an extra -OH group
c. RNA can allow triple base pairing
d. RNA contains phosphate group - CORRECT ANSWER - d. RNA contains phosphate
group
The H2A and H2B
a. Bind with linker DNA
b. Form tetramers
c. Form dimers
d. Are the same protein in two different forms - CORRECT ANSWER - c. Form dimers
The DNA fragment wrapping around the histone core of a nucleosome
a. Is about 50 bp
b. Is about 147 bp
c. Varies in length in different cells
d. Varies in length substantially among different species - CORRECT ANSWER - b. Is
about 147 bp
Which of the following is false?
a. The number of H2A and H2B are always the same in regular nucleosome
