Question 1

Briefly describe the Meselson and Stahl experiment that indicated that DNA replication is semiconservative

Accepted Answer

Meselson and Stahl grew bacteria in the presence of 15N, or "heavy" nitrogen. They rapidly replaced the 15N media with 14N, or "light" nitrogen. DNA was extracted at various intervals during the growth of the bacteria, representing different generations. Meselson and Stahl examined the DNA using density-gradient centrifugation and observed that no "heavy" DNA was present in the first generation, but that the DNA was intermediate between light and heavy. After the second generation, there were equal amounts of intermediate and light. This confirmed that one strand of the parent DNA is present in each daughter strand of replicated DNA.

Question 2

The form of DNA that is the narrowestbut having the longest pitch per turn of helix is the:

Accepted Answer

A)  A form 
B)  B form 
C)  C form 
D)  Z form 
E)  None of the above. 
A)  A form 
B)  B form 
C)  C form 
D)  Z form 
E)  None of the above. D

Question 3

Compare and contrast the three forms of DNA with respect to handedness and hydration state.

Accepted Answer

The Watson and Crick model of DNA is known as B-DNA and is a right-handed helix. A-DNA is also a right-handed helix, but is a less hydrated form. Z-DNA is a left-handed helix characterized by a zigzag arrangement of the backbone phosphoryl groups.

Question 4

A nitrogen containing an aromatic base attached to a ribose is a __________________.

Accepted Answer

The answer of A nitrogen containing an aromatic base attached...

Question 5

Why is there a major and a minor groove in DNA?

Accepted Answer

The major and minor grooves arise becaus

Question 6

Choose the correct answer from the list below. Not all of the answers will be used.
-The axis of a double helix can be twisted by a mechanism called _______________.

Accepted Answer

A) supercoiling 
B) DNA 
C) 5` → 3` 
D) circular 
E) stem loop
F)B-DNA
G)retroviruses
H)exon
I)Erwin Chargaff
J)histones
K)RNA
L)Rosalind Franklin
M)A-DNA
N)3` → 5` 
A) supercoiling 
B) DNA 
C) 5` → 3` 
D) circular 
E) stem loop
F)B-DNA
G)retroviruses
H)exon
I)Erwin Chargaff
J)histones
K)RNA
L)Rosalind Franklin
M)A-DNA
N)3` → 5`

Question 7

The difference in RNA bases compared to DNA bases is:

Accepted Answer

A)  RNA contains A instead of T. 
B)  RNA contains U instead of G. 
C)  RNA contains U instead of T. 
D)  RNA contains A instead of U. 
E)  None of the above. 
A)  RNA contains A instead of T. 
B)  RNA contains U instead of G. 
C)  RNA contains U instead of T. 
D)  RNA contains A instead of U. 
E)  None of the above.

Question 8

How does a nucleotide differ from a nucleoside?

Accepted Answer

A)  Nucleosides are found in DNA, whereas nucleotides are found in RNA. 
B)  Purines are only found in nucleotides. 
C)  Nucleosides contain only deoxyribose sugars. 
D)  A nucleotide is a nucleoside with a phosphate ester linked to the sugar . 
E)  None of the above. 
A)  Nucleosides are found in DNA, whereas nucleotides are found in RNA. 
B)  Purines are only found in nucleotides. 
C)  Nucleosides contain only deoxyribose sugars. 
D)  A nucleotide is a nucleoside with a phosphate ester linked to the sugar . 
E)  None of the above.

Question 9

The shorthand notation pApCpG denotes that:

Accepted Answer

A)  a phosphate is attached to the 5` of the adenosine nucleotide unit. 
B)  a phosphate is attached to the 3` of the guanine nucleotide unit. 
C)  the cytosine nucleotide has a free hydroxyl group. 
D)  A and C. 
E)  All of the above. 
A)  a phosphate is attached to the 5` of the adenosine nucleotide unit. 
B)  a phosphate is attached to the 3` of the guanine nucleotide unit. 
C)  the cytosine nucleotide has a free hydroxyl group. 
D)  A and C. 
E)  All of the above.

Question 10

Describe the DNA helix proposed by Watson and Crick.

Accepted Answer

The DNA model proposed by Watson and Cri

Question 11

Proteins that bind to DNA are rich the amino acids __________________ and __________________.

Accepted Answer

The answer of Proteins that bind to DNA are rich...

Question 12

The chemical forces that contribute to the stability of the DNA due to the base stacking present in the DNA helix are:

Accepted Answer

A)  hydrogen bonds. 
B)  van der Waals interactions. 
C)  disulfide bonds. 
D)  C and C. 
E)  None of the above. 
A)  hydrogen bonds. 
B)  van der Waals interactions. 
C)  disulfide bonds. 
D)  C and C. 
E)  None of the above.

Question 13

Choose the correct answer from the list below. Not all of the answers will be used.
-The stable genetic information passed on from one generation to the next is _______________.

Accepted Answer

A) supercoiling 
B) DNA 
C) 5` → 3` 
D) circular 
E) stem loop
F)B-DNA
G)retroviruses
H)exon
I)Erwin Chargaff
J)histones
K)RNA
L)Rosalind Franklin
M)A-DNA
N)3` → 5` 
A) supercoiling 
B) DNA 
C) 5` → 3` 
D) circular 
E) stem loop
F)B-DNA
G)retroviruses
H)exon
I)Erwin Chargaff
J)histones
K)RNA
L)Rosalind Franklin
M)A-DNA
N)3` → 5`

Question 14

What role does a nucleosome play in DNA structure?

Accepted Answer

A nucleosome consists of approximately 2

Question 15

The process of rehybridizing melted DNA is called:

Accepted Answer

A)  denaturation. 
B)  Tm. 
C)  annealing. 
D)  dehybridization. 
E)  replication. 
A)  denaturation. 
B)  Tm. 
C)  annealing. 
D)  dehybridization. 
E)  replication.

Question 16

How many different sequence possibilities are there for a DNA polymer that is 10 bases long?

Accepted Answer

A)  262,13232 
B)  320 
C)  32,000 
D)  1,048,576 
E)  100,000 
A)  262,13232 
B)  320 
C)  32,000 
D)  1,048,576 
E)  100,000

Question 17

Draw two nucleotides in DNA, showing the linkage between the sugars.

Accepted Answer

The 3` oxygen of one nucleotide is linke

Question 18

Replication takes place in which manner?

Accepted Answer

A)  conservative 
B)  random 
C)  semiconservative 
D)  N-linked 
E)  None of the above. 
A)  conservative 
B)  random 
C)  semiconservative 
D)  N-linked 
E)  None of the above.

Question 19

What are topoisomers of DNA?

Accepted Answer

Topoisomers, or topological isomers, are

Question 20

The __________________ effect stabilizes the structure of DNA, resulting in more polar surfaces being exposed to the aqueous media.

Accepted Answer

The answer of The __________________ effect stabilizes the structure of...

Exam 33: The Structure of Informational Macromolecules: Dna and Rna

Briefly describe the Meselson and Stahl experiment that indicated that DNA replication is semiconservative

The form of DNA that is the narrowestbut having the longest pitch per turn of helix is the:

Compare and contrast the three forms of DNA with respect to handedness and hydration state.

A nitrogen containing an aromatic base attached to a ribose is a __________________.

Why is there a major and a minor groove in DNA?

Choose the correct answer from the list below. Not all of the answers will be used. -The axis of a double helix can be twisted by a mechanism called _______________.

The difference in RNA bases compared to DNA bases is:

How does a nucleotide differ from a nucleoside?

The shorthand notation pApCpG denotes that:

Describe the DNA helix proposed by Watson and Crick.

Proteins that bind to DNA are rich the amino acids __________________ and __________________.

The chemical forces that contribute to the stability of the DNA due to the base stacking present in the DNA helix are:

Choose the correct answer from the list below. Not all of the answers will be used. -The stable genetic information passed on from one generation to the next is _______________.

What role does a nucleosome play in DNA structure?

The process of rehybridizing melted DNA is called:

How many different sequence possibilities are there for a DNA polymer that is 10 bases long?

Draw two nucleotides in DNA, showing the linkage between the sugars.

Replication takes place in which manner?

What are topoisomers of DNA?

The __________________ effect stabilizes the structure of DNA, resulting in more polar surfaces being exposed to the aqueous media.

Biochemistry and the Unity of Life

Water, Weak Bonds, and the Generation of Order Out of Chaos

Amino Acids

Protein Three-Dimensional Structure

Techniques in Protein Biochemistry

Basic Concepts of Enzyme Action

Kinetics and Regulation

Mechanisms and Inhibitors

Hemoglobin: an Allosteric Protein

Carbohydrates

Lipids

Membrane Structure and Function

Signal Transduction Pathways

Digestion: Turning a Meal Into Cellular Biochemicals

Metabolism: Basic Concepts and Design

Glycolysis

Gluconeogenesis

Preparation for the Cycle

Harvesting Electrons From the Cycle

The Electron Transport Chain

The Proton-Motive Force

The Light Reactions

The Calvin Cycle

Glycogen Degradation

Glycogen Synthesis

The Pentose Phosphate Pathway

Fatty Acid Degredation

Fatty Acid Synthesis

Lipid Synthesis

Amino Acid Degradation and the Urea Cycle

Amino Acids Synthesis

Nucleotide Metabolism

DNA Replication

DNA Repair and Recombination

RNA Synthesis and Regulation in Prokaryotes

Gene Expression in Eukaryotes

RNA Processing in Eukaryotes

The Genetic Code

The Mechanism of Protein Synthesis

Recombinant DNA Techniques

Filters

Proteins that bind to DNA are rich the amino acids and .