Multiple Choice Questions

Use Chargaff's rules to predict the missing values for E. coli, human, and ox DNA. Round your answers to the nearest whole number.
  • The data suggest that A would always pair with T and G would always pair with C in a DNA molecule.
  • E.coli- Cytosine: 25.3- Thymine: 24.0Human- Guanine: 19.8- Cytosine: 19.8Ox- 21.0- 21.0- 29.0
  • sugar with two, and not three, oxygen atoms
  • - nitrogenous bases- sugars- phosphate groups
In this activity, you will demonstrate your understanding of antiparallel elongation at the replication forks. Keep in mind that the two strands in a double helix are oriented in opposite directions, that is, they are antiparallel.Drag the arrows onto the diagram below to indicate the direction that DNA polymerase III moves along the parental (template) DNA strands at each of the two replication forks. Arrows can be used once, more than once, or not at all.
  • a) 14N/15Nb) 14N/15Nc) 14N/14N 15N/15N
  • a) ->b) ->c) <-d) <-
  • h b c d a g f e
  • labeled DNA ... DNA
If Chargaff's equivalence rule is valid, then hypothetically we could extrapolate this to the combined genomes of all species on Earth (as if there were one huge Earth genome). In other words, the total amount of A in every genome on Earth should equal the total amount of T in every genome on Earth. Likewise, the total amount of G in every genome on Earth should equal the total amount of C in every genome on Earth.Calculate the average percentage for each base in your completed table. Do Chargaff's equivalence rules still hold true when you consider those six species together?
  • Yes, because the %A approximately equals the %T and the %G approximately equals the %C in both species.
  • Hershey and Chase
  • Yes, the average for A approximately equals the average for T, and the average for G approximately equals the average for C.
  • phosphate group
What are the chemical components of a DNA molecule?Select all that apply.- nitrogenous bases- amino acids- sugars- proteins- phosphate groups
  • They are formed on the lagging strand of DNA.
  • DNA polymerase can assemble DNA only in the 5' to 3' direction
  • - nitrogenous bases- sugars- phosphate groups
  • DNA is usually double-stranded, whereas RNA is usually single-stranded.
The diagram below shows a replication bubble with synthesis of the leading and lagging strands on both sides of the bubble. The parental DNA is shown in dark blue, the newly synthesized DNA is light blue, and the RNA primers associated with each strand are red. The origin of replication is indicated by the black dots on the parental strands.Rank the primers in the order they were produced. If two primers were produced at the same time, overlap them.
  • a) 5' endb) hydrogen bondc) 3' endd) deoxyribose sugare) nitrogenous basef) phosphate groupg) 3' endh) 5' end
  • thymine ... cytosine
  • a DNA double helix
  • h b c d a g f e
As the two parental (template) DNA strands separate at a replication fork, each of the strands is separately copied by a DNA polymerase III (orange), producing two new daughter strands (light blue), each complementary to its respective parental strand. Because the two parental strands are antiparallel, the two new strands (the leading and lagging strands) cannot be synthesized in the same way.Drag each phrase to the appropriate bin depending on whether it describes the synthesis of the leading strand, the synthesis of the lagging strand, or the synthesis of both strands.
  • second replication- both are equally high (go up to about 5)third replication- left is higher, but only goes up to about 7.5fourth replication- left is higher and goes up to about 9
  • - DNA stores genetic information in the sequence of its bases.- DNA can be replicated by making complementary copies of each strand.- DNA can change. Errors in copying can result in changes in the DNA sequence that could be inherited by future generations.
  • leading strand- made continuously- only one primer needed- daughter strand elongates toward replication forklagging strand- made in segments- multiple primers needed- daughter strand elongates away from replication forkboth strands- synthesized 5' to 3'
  • helicase:- breaks H-bonds between bases- binds at the replication forktopoisomerase- binds ahead of the replication fork- breaks covalent bonds in DNA backbonesingle-strand binding protein- prevents H-bonds between bases- binds after the replication fork
Hershey and Chase used _____ to radioactively label the T2 phage's proteins.Hershey and Chase used _____ to radioactively label the T2 phage's proteins.- 92U- 222Ra- 32P- 35S- 14C
  • ligase
  • - nitrogenous bases- sugars- phosphate groups
  • 35S
  • DNA
In the 1950s, when Watson and Crick were working on their model of DNA, which concepts were well accepted by the scientific community?Select all that apply.- Genes are located on chromosomes.- Genes are made of DNA.- Chromosomes are found in the nucleus.- Chromosomes are made up of protein and nucleic acid.
  • Yes, because the %A approximately equals the %T and the %G approximately equals the %C in both species.
  • a) 5' endb) hydrogen bondc) 3' endd) deoxyribose sugare) nitrogenous basef) phosphate groupg) 3' endh) 5' end
  • - Genes are located on chromosomes- Chromosomes are found in the nucleus- Chromosomes are made up of protein and nucleic acid.
  • The data suggest that A would always pair with T and G would always pair with C in a DNA molecule.
The radioactive isotope 32P labels the T2 phage's _____.The radioactive isotope 32P labels the T2 phage's _____.- head- base plate- protein coat- DNA- tail
  • 5' to 3'
  • DNA
  • True
  • 35S
Nucleic acids are assembled in the _____ direction.Nucleic acids are assembled in the _____ direction.- 5' to 1'- 1' to 5'- 5' to 3'- 2' to 3'- 4' to 5'
  • GAYTCCG
  • 5' to 3'
  • algae gene
  • 1' ... 5'
Synthesis of the lagging strandIn contrast to the leading strand, the lagging strand is synthesized as a series of segments called Okazaki fragments. The diagram below illustrates a lagging strand with the replication fork off-screen to the right. Fragment A is the most recently synthesized Okazaki fragment. Fragment B will be synthesized next in the space between primers A and B.Drag the labels to their appropriate locations in the flowchart below, indicating the sequence of events in the production of fragment B. (Note that pol I stands for DNA polymerase I, and pol III stands for DNA polymerase III.)
  • E.coli- Cytosine: 25.3- Thymine: 24.0Human- Guanine: 19.8- Cytosine: 19.8Ox- 21.0- 21.0- 29.0
  • 2) pol III moves...3) pol I binds to 5'...4) pol I replaces primer...5) DNA ligase...
  • a) ->b) ->c) <-d) <-
  • a) 5' endb) hydrogen bondc) 3' endd) deoxyribose sugare) nitrogenous basef) phosphate groupg) 3' endh) 5' end
In the accompanying image, a nucleotide is indicated by the letter _____.
  • 35S
  • DNA
  • B
  • C
After allowing phages grown with bacteria in a medium that contained 32P and 35S, Hershey and Chase used a centrifuge to separate the phage ghosts from the infected cell. They then examined the infected cells and found that they contained _____, which demonstrated that _____ is the phage's genetic material.After allowing phages grown with bacteria in a medium that contained 32P and 35S, Hershey and Chase used a centrifuge to separate the phage ghosts from the infected cell. They then examined the infected cells and found that they contained _____, which demonstrated that _____ is the phage's genetic material.- labeled protein ... DNA- labeled DNA .... protein- labeled DNA ... DNA- labeled DNA ... labeled protein- labeled protein .... protein
  • a) ->b) ->c) <-d) <-
  • thymine ... cytosine
  • each new DNA double helix consists of one old DNA strand and one new DNA strand
  • labeled DNA ... DNA
In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand.In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand.- cytosine ... thymine- uracil ... cytosine- guanine ... adenine- cytosine ... uracil- thymine ... cytosine
  • thymine ... cytosine
  • a) 5' endb) hydrogen bondc) 3' endd) deoxyribose sugare) nitrogenous basef) phosphate groupg) 3' endh) 5' end
  • a) ->b) ->c) <-d) <-
  • h b c d a g f e
In DNA replication in bacteria, the enzyme DNA polymerase III (abbreviated DNA pol III) adds nucleotides to a template strand of DNA. But DNA pol III cannot start a new strand from scratch. Instead, a primer must pair with the template strand, and DNA pol III then adds nucleotides to the primer, complementary to the template strand. Each of the four images below shows a strand of template DNA (dark blue) with an RNA primer (red) to which DNA pol III will add nucleotides.In which image will adenine (A) be the next nucleotide to be added to the primer?
  • thymine ... cytosine
  • a) ->b) ->c) <-d) <-
  • helicase:- breaks H-bonds between bases- binds at the replication forktopoisomerase- binds ahead of the replication fork- breaks covalent bonds in DNA backbonesingle-strand binding protein- prevents H-bonds between bases- binds after the replication fork
  • C G CT G C G A
The DNA double helix is composed of two strands of DNA; each strand is a polymer of DNA nucleotides. Each nucleotide consists of a sugar, a phosphate group, and one of four nitrogenous bases. The structure and orientation of the two strands are important to understanding DNA replication.Drag the labels to their appropriate locations on the diagram below. Pink labels can be used more than once.
  • a) 5' endb) hydrogen bondc) 3' endd) deoxyribose sugare) nitrogenous basef) phosphate groupg) 3' endh) 5' end
  • helicase:- breaks H-bonds between bases- binds at the replication forktopoisomerase- binds ahead of the replication fork- breaks covalent bonds in DNA backbonesingle-strand binding protein- prevents H-bonds between bases- binds after the replication fork
  • thymine ... cytosine
  • - DNA stores genetic information in the sequence of its bases.- DNA can be replicated by making complementary copies of each strand.- DNA can change. Errors in copying can result in changes in the DNA sequence that could be inherited by future generations.
What did the structure of DNA's double helix suggest about DNA's properties?Select all that apply.- DNA stores genetic information in the sequence of its bases.- DNA is found in the nucleus.- DNA can be replicated by making complementary copies of each strand.- DNA can change. Errors in copying can result in changes in the DNA sequence that could be inherited by future generations.
  • - DNA stores genetic information in the sequence of its bases.- DNA can be replicated by making complementary copies of each strand.- DNA can change. Errors in copying can result in changes in the DNA sequence that could be inherited by future generations.
  • leading strand- made continuously- only one primer needed- daughter strand elongates toward replication forklagging strand- made in segments- multiple primers needed- daughter strand elongates away from replication forkboth strands- synthesized 5' to 3'
  • a) 5' endb) hydrogen bondc) 3' endd) deoxyribose sugare) nitrogenous basef) phosphate groupg) 3' endh) 5' end
  • - nitrogenous bases- sugars- phosphate groups
0 h : 0 m : 1 s

Multiple Choice Questions
Answered Not Answered Not Visited Correct : 0 Incorrect : 0