Deck 7: DNA Structure and Replication

Question 1

In addition to the base,what are the other components of a nucleotide?

A) sugar and polymerase
B) phosphate and sugar
C) phosphate and polymerase
D) phosphate and helix
E) helix and sugar

Answer 1

B

Question 2

You are studying the DNA profile of an individual,and you are looking at the results for a chromosome with just one STR site.How many bands will you see?

A) 1
B) 2
C) either 1 or 2
D) 3
E) either 1,2,or 3

Answer 2

C

Question 3

Gel electrophoresis separates DNA for profiling based on the _____.

A) shape of the double helix
B) size (length)
C) number of PCR products
D) number of chromosomes
E) gender of the individual

Answer 3

B

Question 4

You can detect DNA that is specifically from the X chromosome in a DNA sample from a person.Why can't you definitively determine the sex of that person (male or female)from the presence of the X chromosome?

A) Males and females have different types of X chromosomes.
B) Both males and females have an X chromosome.
C) You would have to check for the presence of a Y chromosome.
D) Both males and females have an X chromosome and you would have to check for the presence of a Y chromosome.
E) Males and females have different types of Y chromosomes.

Question 5

An individual's STR may vary from the same STR of another individual by the _____

A) order of nucleotides.
B) specific bases present.
C) specific chromosomal location of the STR.
D) number of times a particular sequence is repeated.
E) number of coding regions.

Question 6

Which statement about PCR is true?

A) DNA polymerase is the enzyme that copies DNA in PCR.
B) Primers are not necessary for PCR.
C) PCR does not require nucleotides.
D) PCR does not generate a complementary DNA strand.
E) PCR can only replicate a few strands of DNA and not specific regions.

Question 7

What is the purpose of careful primer design before PCR?

A) Primers indicate the section of DNA that will be amplified and mark where DNA polymerase begins replication.
B) Primers allow for complementary nucleotides to be added to the new strand of DNA.
C) Primers are used to separate the original DNA strand to give polymerase a place to start replication.
D) Primers are the nucleotides that are used in a PCR reaction to form DNA strands.
E) Primers are enzymes that speed up the rate of a PCR reaction.

Question 8

Which person would have DNA that is least similar to yours?

A) your mother
B) your mother's brother
C) your older sibling
D) your identical twin
E) your nonidentical twin

Question 9

Human red blood cells are enucleated (i.e. ,they do not have nuclei).Is it possible to isolate DNA from red blood cells? Why or why not?

A) Yes,the genomic DNA is found only in enucleated cells.
B) Yes,genomic DNA is found in all cells.
C) No,human cells do not have nuclei.
D) Yes,because genomic DNA can be isolated from other cellular locations.
E) No,the genomic DNA is found only in nucleated cells.

Question 10

Which phrase represents genetic variation between individuals?

A) whether or not G pairs with C or T
B) the number of STRs in their genomes
C) the number of chromosomes in the nucleus
D) the number of chromosomes received from each parent
E) none of these

Question 11

If you start with one copy of a DNA fragment,how many rounds of PCR will it take to end up with a total of 32 copies?

A) 8
B) 5
C) 4
D) 16
E) 31

Question 12

What naturally occurring process does PCR mimic in a test tube?

A) DNA condensation
B) transcription
C) genomics
D) DNA replication
E) polymerization

Question 13

Complete the following statements regarding the steps necessary to copy a DNA sequence during PCR:
1)The two original strands of the DNA molecule can be separated by _____.
2)The enzyme _____ "reads" each template strand and adds _____ to make a new strand.

A) 1)heat,2)primase;complementary nucleotides
B) 1)cooling,2)DNA polymerase;any nucleotides
C) 1)forensics,2)DNA polymerase;complementary nucleotides
D) 1)DNA polymerase,2)primase;any nucleotides
E) 1)heat,2)DNA polymerase;complementary nucleotides

Question 14

The _____ chromosomes in a human cell from inside the cheek are found in the _____.

A) 46;cytoplasm
B) 23;nucleus
C) 24;cytoplasm
D) 46;nucleus
E) 22;nucleus

Question 15

If the sequence of one strand of DNA is AGTCTAGC,what is the sequence of the complementary strand?

A) AGTCTAGC
B) CGATCTGA
C) TCAGATCG
D) GTCGACGC
E) GCTAGACT

Question 16

Which of these is NOT a nucleotide found in DNA?

A) adenine (A)
B) thymine (T)
C) cytosine (C)
D) guanine (G)
E) uracil (U)

Question 17

DNA replication is said to be semiconservative because a newly replicated,double-stranded DNA molecules consists of _____.

A) two old strands
B) two new strands
C) one old strand and one new strand
D) two strands,each with a mixture of old and new DNA
E) different mixes of strands,depending on the cell type

Question 18

Which STR will have migrated farthest through an electrophoresis gel?

A) GAAG repeated twice
B) GAAG repeated three times
C) AGCT repeated five times
D) GAAG repeated seven times
E) AGCT repeated seven times

Question 19

Each chromosome contains _____

A) DNA only.
B) proteins only.
C) DNA and proteins.
D) the same number of genes and STRs.
E) the entire genome of a cell.

Question 20

The entire sequence of DNA in a cell used for DNA profiling is called the _____.

A) chromosome
B) X chromosome
C) genome
D) Y chromosome
E) nucleus

Question 21

Choose the statement(s)that correctly describe the organization of DNA.______ is/are made of ______,and ______ contain(s)many ______.

A) DNA;chromosomes;chromosomes;genes
B) Chromosomes;DNA;chromosomes;genes
C) DNA;genes;genes;chromosomes
D) Genes;DNA;chromosomes;genes
E) Both B and D

Question 22

DNA replication is said to be semiconservative because a newly replicated,double-stranded DNA molecule consists of

A) two old strands.
B) two new strands.
C) one old strand and one new strand.
D) two strands,each with a mixture of old and new DNA.
E) any of the answers are correct,depending on the cell type

Question 23

Where are chromosomes located in eukaryotic cells?

A) cytoplasm
B) nucleus
C) specialized protein sacs
D) tightly wrapped together
E) centromeres

Question 24

An individual's DNA is

A) different in every cell.
B) varies depending on cell type.
C) identical in all cells.
D) identical only in some cells.
E) identical to their mother's DNA.

Question 25

In addition to the base,what are the other components of a nucleotide?

A) sugar and polymerase
B) phosphate group and sugar
C) phosphate group and polymerase
D) phosphate group and helix
E) helix and sugar

Question 26

You are investigating a crime.The DNA profile database has no perfect matches to the DNA collected at the crime scene.However,one profile in the database has at least one band in common with the crime scene DNA at every STR site.Which statement is the most likely conclusion can you draw?

A) A high probability exists that the DNA in the database and the DNA collected at the crime scene are from the same person.
B) A parent-child relationship exists between the DNA collected at the crime scene and the DNA in the database.
C) A sibling relationship exists between the DNA collected at the crime scene and the DNA in the database.
D) No close family relationship exists between the DNA collected at the crime scene and the DNA in the database.
E) No logical conclusion can be drawn from these results.

Question 27

Cells in your kidneys produce different proteins and carry out different tasks than cells in your brain.How is that possible?

A) Kidney and brain cells have completely different DNA.
B) Kidney and brain cells have some DNA that's the same and some that's different.
C) Kidney and brain cells have the same DNA but use different genes.
D) Kidney cells have Mom's DNA,but brain cells have Dad's DNA.
E) Kidney cells use only some of the genes in the DNA,but brain cells use all of the genes.

Question 28

While studying the cells of a newly discovered fungus,you notice that its organelles resemble those of most eukaryotes,but some of their shapes are a little different.Although you're pretty sure you can identify each organelle,you analyze its chemical composition just to make sure.One organelle is shaped like a ball,and it is composed of proteins,membranes,and nucleic acids.That organelle is most likely the

A) nucleus.
B) endoplasmic reticulum.
C) chromosome.
D) Golgi body.
E) lysosome.

Question 29

What is a chromosome?

A) a large piece of DNA found within the cytoplasm of a cell
B) a large protein that surrounds and protects DNA
C) a large,tightly bound piece of DNA and protein found in the nucleus of cells
D) a starting material used for producing DNA in a cell
E) a term used to describe all the genetic material found within a person's cells

Question 30

Red blood cells go through some special modifications as they mature.As a final step,the cells lose their nucleus.Which of the following is a likely consequence?

A) Red blood cells have extra genes not found in other cells.
B) Red blood cells have less DNA than other cells.
C) Red blood cells have less carbohydrate than other cells.
D) Red blood cells have more DNA than other cells.
E) Red blood cells are larger than most other cells.

Question 31

What is a genome?

A) the complete set of genetic material encoded within the DNA of an organism
B) the total number of base pairs within a DNA sequence
C) a short sequence of DNA that codes for a particular characteristic
D) the total amount of RNA within an organism
E) strands of DNA wound around proteins;humans have 23 pairs

Question 32

The _____ chromosomes in a typical human cell are found in the_____.

A) 46;cytoplasm
B) 23;nucleus
C) 24;cytoplasm
D) 46;nucleus
E) 22;nucleus

Question 33

Liver cells and kidney cells do different tasks because they

A) start off with the same DNA,but destroy unnecessary genes.
B) start off with the same DNA,but gain different genes from stem cells.
C) contain completely different DNA and genes.
D) contain the same DNA but use different genes.
E) have different sequences of DNA in their genes.

Question 34

How many STRs are typically used to create a profile in forensic investigations?

A) 10
B) 2
C) 5
D) 15
E) 25

Question 35

Each chromosome contains

A) DNA only.
B) proteins only.
C) DNA and proteins.
D) the same number of genes and STRs.
E) the entire genome of a cell.

Question 36

DNA evidence can give an investigator information regarding which of the following?

A) family relationships between suspects
B) identity of an individual based on a profile
C) locations of an individual
D) family relationships between suspects and the locations of an individual
E) family relationships between suspects and the identity of an individual based on a profile

Question 37

Which of the following is not a nucleotide found in DNA?

A) adenine (A)
B) thymine (T)
C) cytosine (C)
D) guanine (G)
E) uracil (U)

Question 38

An individual's STR may vary from the same STR of another individual by

A) the order of nucleotides.
B) the specific bases present.
C) the specific chromosomal location of the STR.
D) the number of times the sequence is repeated.
E) the number of coding regions.

Question 39

What is DNA?

A) a molecule that is passed down to children from the father but not the mother
B) a molecule found only in blood
C) a molecule common to all life forms
D) a molecule found only in mammals
E) a molecule made of a single strand of nucleotides

Question 40

Which of the following statements about PCR is true?

A) DNA polymerase is the enzyme that copies DNA in PCR.
B) Primers are not necessary for PCR.
C) PCR does not require nucleotides.
D) PCR does not generate a complementary DNA strand.
E) PCR can make only a few copies of a DNA molecule.

Question 41

Identify the correct nucleotide base pairing.

A) A-C;G-T
B) A-G;C-T
C) A-T;G-C
D) A-A;T-T
E) A-G;A-C

Question 42

DNA is called a double helix because

A) two bases are the rungs.
B) the bases are complementary paired.
C) two DNA strands twist together.
D) one DNA strand binds to a sugar.
E) a DNA strand folds into an alpha helix.

Question 43

Which of the following statements does NOT accurately describe human DNA?

A) Human DNA is a unique combination of DNA inherited from both parents.
B) Males receive one X chromosome from their mother.
C) Females receive two X chromosomes from their mother.
D) Humans have 22 pairs of chromosomes and two gender chromosomes.
E) Human DNA is located within the nucleus.

Question 44

DNA can be visualized as a ladder.Which parts would be the rungs (where you step)and which would be the stringers (the sides where you hold on)?

A) The sugars and bases are rungs,and the phosphates are stringers.
B) The phosphates and bases are rungs,and the sugars are stringers.
C) The H-bonded sugars are rungs,and the phosphate bases are stringers.
D) The bases are rungs,and the sugars and phosphates are stringers.
E) The bases are the rungs,and the sugars the stringers.

Question 45

What are nucleotides?

A) subunits found in proteins
B) subunits that combine to make DNA
C) molecules made of a sugar,a protein,and a base
D) molecules around which chromosomes coil
E) machinery the cell uses to copy its DNA

Question 46

Bases holding two single strands of DNA together into a double strand of DNA interact through ___________ bonds.

A) covalent
B) hydrogen
C) ionic
D) chemical
E) carbon

Question 47

Which is the best description of how nucleotides are attached to make DNA?
Nucleotides are attached to each other ________.

A) phosphate to phosphate
B) sugar to sugar
C) phosphate to sugar
D) base to base
E) base to phosphate

Question 48

DNA is a type of molecule called a _________.Its smaller parts are called __________.

A) protein;amino acids
B) deoxyribonucleic acid;amino acids
C) deoxyribonucleic acid;nucleotides
D) nucleotide;deoxyribonucleic acids
E) protein;nucleotides

Question 49

What is the "double helix" when referring to the structure of DNA?

A) two strands of linked nucleotides that are twisted around each other
B) two strands of linked nucleotides that fold back and forth like an accordion
C) four strands of linked nucleotides that are bound by phosphate groups
D) four strands of linked nucleotides that are bound by sugar groups
E) two chromosomes that are twisted around each other

Question 50

What is the significance of the "23rd pair" of chromosomes in humans?

A) It is inherited only from the mother.
B) It is inherited only from the father.
C) It doesn't exist;there are only 22 pairs.
D) It doesn't contain thymine.
E) It determines a person's sex.

Question 51

Why is DNA called a "double helix"?

A) It has two strands of nucleotides twisted around each other.
B) It has two strands of nucleotides,folded back and forth like an accordion.
C) It has helical bases,arranged together in complementary pairs.
D) It has four strands of nucleotides bound together with sugars.
E) It has two chromosomes,linked and twisted together.

Question 52

What is the complementary base-pairing rule?

A) Adenine will always pair with guanine.
B) Guanine will always pair with thymine.
C) Adenine can pair with either guanine or thymine.
D) A nucleotide can base-pair to any other nucleotide using hydrogen bonds.
E) Adenine will always pair with thymine,and cytosine will always pair with guanine.

Question 53

The width (diameter)of the DNA helix normally varies a lot,depending on which bases are paired together at that location.

A) True
B) False

Question 54

You are hired as a research assistant to help determine the genome of a wild onion plant.At the end of this project,you expect to have the

A) sequence of all of its genes.
B) sequence of all of its DNA.
C) sequence of all of its proteins.
D) total amount of RNA,DNA,and protein in its cells.
E) number of chromosomes in its nucleus.

Question 55

How is the structure of a DNA molecule arranged?

A) Each nucleotide's phosphate group binds to the corresponding phosphate group of another nucleotide.
B) Each nucleotide's sugar group binds to the corresponding sugar group of another nucleotide.
C) Each nucleotide's phosphate group binds to the sugar group of the next nucleotide.
D) Each nucleotide's base binds to the next nucleotide base.
E) Each nucleotide's base binds to the phosphate group of another nucleotide.

Question 56

A science museum hires an interior designer to create a spiral staircase that will represent DNA.The model must be as accurate as possible,but also allow people to climb.You are asked to evaluate the model for scientific accuracy.Which of the following design suggestions would you accept?

A) The steps in the staircase are painted to look like phosphates and sugars.
B) People climbing the stairs will hold onto handrails made of sugars.
C) A support post runs down the very center,representing a string of phosphates.
D) People climbing the staircase will step on pairs of bases.
E) All of the above.

Question 57

Which of the following base pairs would be found in normal DNA?

A) A and T
B) G and G
C) C and A
D) T and C
E) All of the above are correct.

Question 58

A boy's Y chromosome will generally NOT be identical to that of his

A) father.
B) grandfather on father's side of family.
C) great-grandfather on mother's side of family.
D) brothers.
E) All of the above.

Question 59

What is the correct pattern of nucleotide base pairing?

A) adenine-cytosine;guanine-thymine
B) adenine-guanine;cytosine-thymine
C) adenine-thymine;guanine-cytosine
D) adenine-adenine;thymine-thymine
E) adenine-guanine;adenine-cytosine

Question 60

What are nucleotides?

A) enzymes that copy DNA
B) molecules that make up the information contained in DNA
C) molecules that consist of a sugar,a protein,and a base
D) molecules around which chromosomes coil
E) enzymes that split DNA apart so that the DNA can be copied

Question 61

The original strand of DNA used for DNA replication is known as the

A) coding strand.
B) nonconservative strand.
C) messenger strand.
D) template strand.
E) transcription strand.

Question 62

When DNA is copied to make more DNA before cell division,what happens to the original DNA molecule?

A) The original DNA goes to one cell;the new DNA goes to the other cell.
B) Only new DNA is passed on;the original DNA is broken down and recycled.
C) Each of the cells contains half of the original DNA and half new DNA.
D) The original DNA is twisted into a double helix and passed to one of the daughter cells.
E) Either A or C are true,depending on the organism.

Question 63

DNA can generally be extracted from

A) hair.
B) blood.
C) saliva.
D) skin cells.
E) All of the above.

Question 64

What is DNA polymerase?

A) an enzyme that breaks DNA down into fragments
B) an enzyme that deletes specific regions of DNA
C) an enzyme involved in DNA replication that binds to DNA and facilitates the formation of a new strand of DNA
D) an enzyme that allows the chromosomes to coil around proteins so that the chromosomes can fit into the nucleus
E) an enzyme that removes the sugar molecule from a nucleotide so that the phosphate groups can be linked together

Question 65

To make a copy of DNA,all of the following must occur EXCEPT

A) hydrogen bonds break.
B) adenine pairs with thymine.
C) DNA polymerase binds to the DNA.
D) the old strand is used as a template.
E) the DNA coils to form a replication helix.

Question 66

You start a PCR process with two copies of a DNA molecule.After three cycles of PCR,how many copies of the DNA will be present?

A) 5
B) 6
C) 8
D) 16
E) 27

Question 67

Which of the following is a nucleotide?

A) polymerase
B) guanine
C) phosphate
D) DNA
E) STR region

Question 68

What are the four nucleotide bases that make up the "rungs" of the nucleotide ladder of DNA?

A) adenine,thymine,guanine,cytosine
B) adenine,uracil,guanine,cytosine
C) adenine,thymine,cytosine,phosphate
D) adenine,cytosine,nitrogen,phosphate
E) adenine,cytosine,sugar,phosphate

Question 69

DNA polymerase is an enzyme that

A) breaks DNA down into fragments.
B) deletes specific regions of DNA.
C) makes copies of DNA.
D) tightly winds DNA into chromosomes.
E) removes sugars from nucleotides to link them together.

Question 70

DNA replication results in __________ copies of a cell's genome.

A) two similar
B) two identical
C) four similar
D) four identical
E) None of the above.

Question 71

PCR stands for

A) polymers confer reactants.
B) polymerase chain reaction.
C) polymerase cell reproduction.
D) potential chain reaction.
E) polynucleotide cycling reaction.

Question 72

DNA is made of the following nucleotide bases,EXCEPT

A) adenine.
B) guanine.
C) phosphate.
D) cytosine.
E) thymine.

Question 73

When one DNA molecule is duplicated,the resulting two DNA molecules contain

A) one new and one old strand in each.
B) two new strands in one and two old strands in the other.
C) four new strands in each.
D) four old strands in each.
E) four new strands in one and four old strands in the other.

Question 74

Find the sequence that would base pair correctly with ATTCGGC.

A) ATTCGGC
B) TAAGCCG
C) AUUCGGC
D) UAAGCCG
E) None of the above.

Question 75

The process of DNA replication requires

A) breaking of hydrogen bonds.
B) unwinding of the DNA.
C) enzymes.
D) nucleotides.
E) All of the above.

Question 76

DNA replication occurs

A) in the Golgi.
B) in the cytoplasm.
C) in the nucleus.
D) in lysosomes.
E) in vesicles.

Question 77

You have a segment of DNA with a nucleotide sequence reading AATAGC on one strand.Which of the following nucleotide sequences would match it on the opposite strand?

A) AATAGC
B) CCGCTA
C) GGCGAT
D) TTATCG
E) AAGACG

Question 78

Why is heating a first step in PCR amplification of extracted DNA?

A) The enzyme DNA polymerase works at a higher temperature.
B) The nucleotides bind together at high heat.
C) It is necessary for DNA strands to anneal to each other.
D) It permits hydrogen bonds between DNA strands to dissociate.
E) It is required for primers to bind permanently to the DNA.

Question 79

Which statement about PCR is FALSE?

A) PCR will amplify DNA,even from just a single DNA molecule.
B) Amplification of DNA in a PCR reaction is exponential.
C) PCR works on only a single strand of DNA at a time.
D) PCR uses primers to amplify both DNA strands simultaneously.
E) PCR requires DNA,primers,DNA polymerase,and nucleotides.

Question 80

What is meant by "semiconservative" replication?

A) As the new strands of DNA are formed,the old strands are broken down and recycled.
B) As the new strands of DNA are formed,one of the old strands is broken down and recycled while the other is used as a template for the creation of a new strand.
C) The original strands of DNA are used to make newer strands,resulting in two copies of the DNA,one made entirely of new DNA,the other entirely of old DNA.
D) As DNA replication occurs,two new strands of DNA are produced without use of the original strands.
E) Each newly replicated strand of DNA consists of one original strand and one newly formed strand.