MOLECULAR BIOLOGY (EXAM 1)
QUESTIONS AND ANSWERS 100%
CORRECT
Nucleotide - ANSWER-Monomer of DNA
Nucleoside - ANSWER-Molecule of ribose plus base
2-deoxyribose - ANSWER-sugar that has a H at the 2' C
Ribose - ANSWER-Name of five carbon sugar that is found in RNA
Basepair - ANSWER-Two nucleotides, one with a purine & one with a pyrimidine,
connected by H bonds
Antiparallel means - ANSWER-the two polynucleotide chains/strands run in opposite
directions
What two factors are the main determination of the Tm of DNA - ANSWER-Amount of
G:C's & overall strand length
How many rings do purines & pyrimidines have? - ANSWER-Purines: 2
Pyrimidines:1
The DNA from two different species can often be distinguished by a difference in
the____. - ANSWER-Ratio of A+T to G+C
What is the difference between Uracil & Thymine - ANSWER-Thymine has a methyl
group
What did the X-ray diffraction patterns produced by Rosalind Franklin initially reveal
about the DNA molecule? - ANSWER-It is a helical structure with distinct regularities
You have 340 nm of double stranded B form DNA. How many 360 degree turns are
present in the double helix? - ANSWER-100
You have 340 nm of double stranded B form DNA. How many nucleotides are present?
Be careful! - ANSWER-2000
DNA and RNA both contain phosphate and deoxyribose. (True or False) - ANSWER-
False
, In general, the keto form of thymine is more abundant than the enol form. (True or
False) - ANSWER-True
Left-Handed helical form of DNA - ANSWER-Z-DNA
DNA that results from reduced humidity around the DNA and is more tightly wound -
ANSWER-A-DNA
DNA that most closely resembles the Watson & Crick model - ANSWER-B-DNA
Term used to describe the amount of the double helix crossing over itself - ANSWER-
Writhe
Number of helical turns in a given space - ANSWER-Twist
What are the main RNA secondary structures? - ANSWER-Bulge-loop, hairpin,
pseudoknot, internal loop, and double helix
A closer association between DNA and histones most likely causes___. - ANSWER-
repression in gene expression
Which amino acids of histone N-termini can be acetylated and deacetylated? -
ANSWER-Lysines
RNA can form Beta Sheets (True or False) - ANSWER-False
What forms the major & minor grooves? - ANSWER-Glycosidic bonds
Term used to describe sheer stress protein binding causing an adjacent base to twist -
ANSWER-Propeller twist
Type II topoisomerase found in prokaryotes that relieves stress on unwinding DNA
during replication by negative supercoiling - ANSWER-Gyrase
Catalytically active RNA strands - ANSWER-Ribozymes
Cohesins - ANSWER-Protein that regulates the separation of sister chromatids during
M-phase
Characteristics of Histones (and their tails) - ANSWER--Comprised of 8 subunits
(octamer)
-Tails are enriched with lysine & arginine
-(+) tails mask (-) DNA
-Tails interact with both DNA & other tails
QUESTIONS AND ANSWERS 100%
CORRECT
Nucleotide - ANSWER-Monomer of DNA
Nucleoside - ANSWER-Molecule of ribose plus base
2-deoxyribose - ANSWER-sugar that has a H at the 2' C
Ribose - ANSWER-Name of five carbon sugar that is found in RNA
Basepair - ANSWER-Two nucleotides, one with a purine & one with a pyrimidine,
connected by H bonds
Antiparallel means - ANSWER-the two polynucleotide chains/strands run in opposite
directions
What two factors are the main determination of the Tm of DNA - ANSWER-Amount of
G:C's & overall strand length
How many rings do purines & pyrimidines have? - ANSWER-Purines: 2
Pyrimidines:1
The DNA from two different species can often be distinguished by a difference in
the____. - ANSWER-Ratio of A+T to G+C
What is the difference between Uracil & Thymine - ANSWER-Thymine has a methyl
group
What did the X-ray diffraction patterns produced by Rosalind Franklin initially reveal
about the DNA molecule? - ANSWER-It is a helical structure with distinct regularities
You have 340 nm of double stranded B form DNA. How many 360 degree turns are
present in the double helix? - ANSWER-100
You have 340 nm of double stranded B form DNA. How many nucleotides are present?
Be careful! - ANSWER-2000
DNA and RNA both contain phosphate and deoxyribose. (True or False) - ANSWER-
False
, In general, the keto form of thymine is more abundant than the enol form. (True or
False) - ANSWER-True
Left-Handed helical form of DNA - ANSWER-Z-DNA
DNA that results from reduced humidity around the DNA and is more tightly wound -
ANSWER-A-DNA
DNA that most closely resembles the Watson & Crick model - ANSWER-B-DNA
Term used to describe the amount of the double helix crossing over itself - ANSWER-
Writhe
Number of helical turns in a given space - ANSWER-Twist
What are the main RNA secondary structures? - ANSWER-Bulge-loop, hairpin,
pseudoknot, internal loop, and double helix
A closer association between DNA and histones most likely causes___. - ANSWER-
repression in gene expression
Which amino acids of histone N-termini can be acetylated and deacetylated? -
ANSWER-Lysines
RNA can form Beta Sheets (True or False) - ANSWER-False
What forms the major & minor grooves? - ANSWER-Glycosidic bonds
Term used to describe sheer stress protein binding causing an adjacent base to twist -
ANSWER-Propeller twist
Type II topoisomerase found in prokaryotes that relieves stress on unwinding DNA
during replication by negative supercoiling - ANSWER-Gyrase
Catalytically active RNA strands - ANSWER-Ribozymes
Cohesins - ANSWER-Protein that regulates the separation of sister chromatids during
M-phase
Characteristics of Histones (and their tails) - ANSWER--Comprised of 8 subunits
(octamer)
-Tails are enriched with lysine & arginine
-(+) tails mask (-) DNA
-Tails interact with both DNA & other tails
