Question 1

What is the effect of ionizing radiation on DNA?  
A)faster replication
B)the formation of nucleotide dimers
C)kinks in the DNA molecule
D)breaks in the DNA molecule
E)base pair mismatching

Accepted Answer

Ionizing radiation can cause breaks in the DNA molecule, leading to mutations and potential damage to cells.

Question 2

What is the spontaneous process by which the base-pairing occurs between two strands of DNA?  
A)differentiation
B)duplication
C)hybridization
D)polymerization
E)replication

Accepted Answer

The spontaneous process by which the base-pairing occurs between two strands of DNA is called hybridization, where complementary bases (adenine with thymine, and cytosine with guanine) form hydrogen bonds and join the two strands together. Differentiation refers to the process where cells become specialized, duplication refers to making an exact copy of DNA or an organism, polymerization refers to the formation of a polymer from monomers, and replication refers to the process of making a copy of DNA.

Question 3

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once.
-discovered that the amount of adenine in a DNA molecule was equal to the amount of thymine
A)Chargaff
B)Franklin
C)Watson and Crick
D)Wilkins
E)Hershey and Chase
F)Miescher

Accepted Answer

Chargaff discovered that the amount of adenine in a DNA molecule was equal to the amount of thymine.

Question 4

When two adjacent bases in the same strand of DNA dimerize (form a covalent bond between them),what happens to the DNA?  
A)the original strand of DNA now contains a new DNA sequence
B)the original strand of DNA is kinked, which prevents DNA polymerase from working properly
C)the original strand of DNA is methylated, which causes the bases to mismatch
D)the original strand of DNA is prevented from opening during replication, so this section of DNA will not be replicated
E)the original strand of DNA is unaffected, so no additional mutations arise

Accepted Answer

When adjacent bases in the same strand form a covalent bond, it leads to a structural distortion in the DNA called a thymine dimer. This kink in the DNA helix can prevent DNA polymerase from reading and replicating the DNA properly, leading to mutations or errors in DNA replication.

Question 5

Hybridization of DNA is _____ and is driven entirely by _____.
A)non-spontaneous; ATP
B)non-spontaneous; hydrogen bonding
C)non-spontaneous; glycolysis
D)spontaneous; ATP
E)spontaneous; hydrogen bonding

Accepted Answer

Hybridization of DNA is a spontaneous process that occurs through hydrogen bonding between complementary base pairs. No additional energy source, such as ATP or glycolysis, is required for this process to occur.

Question 6

The most common source of DNA mutation is _____; however,these mistakes are typically corrected.
A)cigarette smoke
B)UV light
C)errors in DNA replication
D)errors in protein synthesis
E)pesticides on the food we eat

Accepted Answer

Errors in DNA replication are the most common source of DNA mutation. During cell division, DNA is replicated and mistakes can occur, resulting in mutations. However, most of these mistakes are corrected by proofreading mechanisms and other DNA repair pathways. Other sources of mutations, such as exposure to UV light or cigarette smoke, can also cause mutations but are not as common as errors during DNA replication.

Question 7

If an error is made during replication that is not caught by DNA polymerase,the most likely is that _____.
A)both strands of DNA will be mutated
B)only the daughter strand will be mutated
C)a mutation that causes cancer will occur
D)DNA ligase will repair the mistake before a mutation occurs
E)DNA replication will stall indefinitely

Accepted Answer

If an error is made during replication that is not caught by DNA polymerase, it means that the mistake has been incorporated into the new daughter strand. The parent strand remains intact. Therefore, only the daughter strand will be mutated.

Question 8

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once.
-proved that DNA,not protein,transmits a full complement of hereditary information
A)Chargaff
B)Franklin
C)Watson and Crick
D)Wilkins
E)Hershey and Chase
F)Miescher

Accepted Answer

Hershey and Chase conducted experiments with bacteriophages (viruses that infect bacteria) and radioactive labeling to demonstrate that DNA, not protein, is the genetic material passed from the viruses to the bacteria, thus carrying the hereditary information.

Question 9

Which enzyme links nucleotides into a new stand of DNA?  
A)DNA ligase
B)DNA mutase
C)DNA polymerase
D)DNA primer
E)DNA replicase

Accepted Answer

DNA polymerase is the enzyme that links nucleotides into a new strand of DNA during DNA replication.

Question 10

Chemicals in tobacco smoke can cause _____.
A)DNA to break into pieces.
B)mispairing of bases.
C)kinking in the DNA molecule.
D)the formation of nucleotide dimers.
E)covalent bonding between adjacent adenine bases.

Accepted Answer

The answer of Chemicals in tobacco smoke can cause _____.
A)DNA...

Question 11

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once.
-discovered that the sequence of DNA differs in different organisms
A)Chargaff
B)Franklin
C)Watson and Crick
D)Wilkins
E)Hershey and Chase
F)Miescher

Accepted Answer

Chargaff discovered that the sequence of DNA differs in different organisms through his research on the base composition of DNA.

Answer: C
 Watson and Crick are credited with discovering the double helix structure of DNA, which they published in a paper in 1953.

Answer: B
 Franklin played a major role in discovering the structure of DNA through her work with X-ray crystallography, which provided crucial data to Watson and Crick.

Answer: D
 Wilkins also contributed to the discovery of the structure of DNA through his work with X-ray crystallography, which he shared with Franklin.

Answer: F
 Miescher was the first person to isolate nucleic acid, which he called "nuclein," from white blood cells in 1869. This laid the foundation for later research on DNA.

Question 12

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once.
-built the first precise model of DNA that implied its method of replication
A)Chargaff
B)Franklin
C)Watson and Crick
D)Wilkins
E)Hershey and Chase
F)Miescher

Accepted Answer

Watson and Crick are credited with building the first precise model of DNA, which suggested a mechanism for its replication. This discovery was pivotal in understanding the molecular basis of inheritance.

Question 13

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once.
-used x-ray diffraction technology to determine that phosphate groups are located on the outside of the DNA molecule,and bases on the inside
A)Chargaff
B)Franklin
C)Watson and Crick
D)Wilkins
E)Hershey and Chase
F)Miescher

Accepted Answer

Franklin used x-ray diffraction technology to determine the structure of DNA.

Answer: C
 Watson and Crick used Franklin's data to propose the double helix structure of DNA.

Answer: A
 Chargaff discovered that the amount of adenine and thymine bases in DNA are equal, as are the amounts of guanine and cytosine bases.

Answer: D
 Wilkins worked with Franklin to obtain the x-ray diffraction data that helped Watson and Crick propose the structure of DNA.

Answer: E
 Hershey and Chase conducted experiments with bacteriophages to provide evidence that DNA is the genetic material.

Answer: F
 Miescher was the first to isolate DNA from white blood cells, but did not determine its structure.

Question 14

The addition of methyl groups to DNA by chemicals in tobacco can cause DNA to _____.
A)replicate
B)polymerize
C)hybridize
D)mutate
E)fragment

Accepted Answer

The addition of methyl groups to DNA by chemicals in tobacco can cause mutations in the DNA.

Question 15

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once.
-along with Watson and Crick,received the Nobel Prize for his contribution to the discovery of DNA's structure
A)Chargaff
B)Franklin
C)Watson and Crick
D)Wilkins
E)Hershey and Chase
F)Miescher

Accepted Answer

Maurice Wilkins, along with James Watson and Francis Crick, was awarded the Nobel Prize in Physiology or Medicine in 1962 for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material. Wilkins' contribution was crucial, especially his work with X-ray diffraction images of DNA, which helped in determining the double helix structure of DNA.

Question 16

Short,single strands of nucleotides that serve as attachment points for DNA polymerase are called _____.
A)primers
B)polymerases 
C)ligases
D)mutations
E)diploids

Accepted Answer

Primers are short, single strands of nucleotides that serve as attachment points for DNA polymerase during DNA replication. Polymerases are enzymes that catalyze the formation of DNA molecules from nucleotides. Ligases are enzymes that catalyze the joining of two DNA strands together. Mutations are changes in the nucleotide sequence of DNA. Diploids are organisms that have two sets of chromosomes.

Question 17

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once.
-this researcher's work suggested that DNA was double helix
A)Chargaff
B)Franklin
C)Watson and Crick
D)Wilkins
E)Hershey and Chase
F)Miescher

Accepted Answer

The answer of Answer the following questions by matching each...

Question 18

Rosalind Franklin died from ovarian cancer at the age of 37.Her cancer was probably caused by DNA mutations that arose from _____.
A)extensive exposure to long wavelength radiation
B)contaminated DNA samples
C)chemical exposure
D)unrepaired DNA replication errors
E)extensive exposure to x-rays

Accepted Answer

Rosalind Franklin is famous for her work on understanding the structure of DNA through X-ray crystallography. However, this also exposed her to extensive amounts of X-ray radiation, which is known to cause DNA damage and potentially lead to cancer. Therefore, it is likely that her cancer was caused by the extensive exposure to X-rays.

Question 19

Repair enzymes _____.
A)repair only mutations that occur in mitochondrial DNA
B)repair only mutations that arise during replication
C)repair only DNA mismatch mutations
D)can only repair mutations that occur prior to replication
E)can only repair mutations that occur after replication

Accepted Answer

The answer of Repair enzymes _____.
A)repair only mutations that occur...

Question 20

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once.
-first described DNA as a substance rich in nitrogen and phosphorus
A)Chargaff
B)Franklin
C)Watson and Crick
D)Wilkins
E)Hershey and Chase
F)Miescher

Accepted Answer

Miescher first described DNA as a substance rich in nitrogen and phosphorus.

Answer: A
 Chargaff discovered that the amount of adenine equals the amount of thymine, and the amount of cytosine equals the amount of guanine, which led to the base pairing rules in DNA.

Answer: B
 Franklin used X-ray crystallography to obtain a high-resolution image of DNA, which provided crucial information for Watson and Crick's discovery of the double helix structure.

Answer: C
 Watson and Crick proposed the double helix structure of DNA, which revolutionized the understanding of genetics.

Answer: D
 Wilkins worked with Franklin to obtain X-ray crystallographic images of DNA, which contributed to the discovery of the double helix structure by Watson and Crick.

Answer: E
 Hershey and Chase performed the famous blender experiment that confirmed DNA as the genetic material in bacteriophages.

Quiz 6: DNA Structure And Function

What is the effect of ionizing radiation on DNA?

What is the spontaneous process by which the base-pairing occurs between two strands of DNA?

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once. -discovered that the amount of adenine in a DNA molecule was equal to the amount of thymine

When two adjacent bases in the same strand of DNA dimerize (form a covalent bond between them) ,what happens to the DNA?

Hybridization of DNA is _ and is driven entirely by _.

The most common source of DNA mutation is _____; however,these mistakes are typically corrected.

If an error is made during replication that is not caught by DNA polymerase,the most likely is that _____.

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once. -proved that DNA,not protein,transmits a full complement of hereditary information

Which enzyme links nucleotides into a new stand of DNA?

Chemicals in tobacco smoke can cause _____.

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once. -discovered that the sequence of DNA differs in different organisms

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once. -built the first precise model of DNA that implied its method of replication

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once. -used x-ray diffraction technology to determine that phosphate groups are located on the outside of the DNA molecule,and bases on the inside

The addition of methyl groups to DNA by chemicals in tobacco can cause DNA to _____.

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once. -along with Watson and Crick,received the Nobel Prize for his contribution to the discovery of DNA's structure

Short,single strands of nucleotides that serve as attachment points for DNA polymerase are called _____.

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once. -this researcher's work suggested that DNA was double helix

Rosalind Franklin died from ovarian cancer at the age of 37.Her cancer was probably caused by DNA mutations that arose from _____.

Repair enzymes _____.

Answer the following questions by matching each term with the most appropriate description.Some choices may be used more than once. -first described DNA as a substance rich in nitrogen and phosphorus