Chp 9
B) ligase
A scientist isolates a cell line characterized by unusual cell division. In these cells, only small fragments of DNA are found. A defective ____ enzyme may be responsible. A) DNA polymerase B) ligase C) primase D) exonuclease
D) Watson and Crick.
DNA structure was proposed by A) Griffith. B) Chargaff. C) Avery. D) Watson and Crick.
C) primase adds an RNA primer
Considering DNA replication along the 5' to 3' template strand, what event takes place first? A) DNA polymerase begins adding RNA nucleotides B) DNA polymerase begins adding DNA nucleotides . C) primase adds an RNA primer D) primase removes the 5' phosphate
A) semiconservative
DNA replication is A) semiconservative. B) conservative. C) dispersive. D) semidispersive
D) 100 million
DNA replication is extremely accurate. Only about one in ____ bases is incorporated incorrectly. A) 100,000 B) 1 million C) 10 million D) 100 million
A) A - T
Energy is required to break the hydrogen bonds holding the bases together. Which pair will be the most difficult to separate? A) A - T B) C - G C) A - C D) G - T
D) ligases
Enzymes called ____ catalyze the formation of covalent bonds that hold together the sugar-phosphate backbone of the DNA molecule. A) helicases B) DNA polymerases C) RNA polymerases D) ligases
C) 3 billion
How many DNA bases make up the human genome? A) 3 thousand B) 3 million C) 3 billion D) 30 billion
B) Okazaki fragments.
If DNA polymerase could add bases in the 3' to 5' direction, there would be no need for A) DNA ligase. B) Okazaki fragments. C) helicase. D) PCR.
D) phage protein enters the host cell.
If Hershey and Chase found S35 in progeny phages rather than P32, their experiment would have demonstrated that A) proteins contain phosphorus. B) DNA contains sulfur. C) phage DNA enters the host cell. D) phage protein enters the host cell.
C) 30%
If a DNA molecule contains 20% A, approximately what percentage of G is present? A) 20% B) 40% C) 30% D) 60%
B) double-stranded DNA
If a nucleic acid is found to contain 20% A and 20% T, the molecule is probably A) single-stranded DNA. B) double-stranded DNA. C) single-stranded RNA. D) double-stranded RNA.
C) 75%
In the Meselson and Stahl experiment, what percentage of the DNA is labeled with light nitrogen after three generations of replication. A) 25% B) 50% C) 75% D) 100%
D) no, PCR copies short sequences of DNA only
Is it possible to use PCR to produce many copies of all DNA of one chromosome? A) yes, if the correct primers are available B) yes, if the telomeres are present C) no, PCR cannot copy DNA, only RNA D) no, PCR copies short sequences of DNA only
A) True
PCR requires knowledge about parts of a target DNA sequence to be amplified. True or false? A) True B) False
C) 3 - 2 - 4 - 5 - 3 - 1
Place in order the following steps involved in PCR:(1) newly synthesized strands act as templates(2) temperature lowered; DNA primers and polymerase added(3) heat separates strands of target DNA(4) complementary base pairing between primers and template(5) DNA nucleotide bases added; new strand synthesized A) 1 - 2 - 3 - 4 B) 3 - 5 - 4 - 2 - 3 - 1 C) 3 - 2 - 4 - 5 - 3 - 1 D) 2 - 3 - 4 - 5 - 2 - 1
C) 5' to 3'
Replication proceeds in a ____ to _____ direction. A) 3' to 3' B) 3' to 5' C) 5' to 3' D) 5' to 5'
D) 32
The number of amplified pieces of DNA equals ____ after five cycles of PCR. A) 5 B) 10 C) 25 D) 32
B) Avery.
The transforming agent was identified as DNA by A) Griffith. B) Avery. C) Hershey and Chase. D) Watson and Crick
C) covalent, pyrmidines.
Ultraviolet radiation damages DNA by causing an extra ____ bond to form between adjacent ____. A) hydrogen, pyrmidines. B) covalent, purines. C) covalent, pyrmidines. D) hydrogen, purines
B) DNA polymerase
Which of the following is not a component of a chromosome? A) histone proteins B) DNA polymerase C) RNA D) chromosomes contain all of the above
D) 5' AAGCGTTT 3'
Which strand below would make the sequence 5' AAACGCTT 3' a double stranded DNA molecule? A) 5' TTTGCGAA 3' B) 5' UUUGCGUU 3' C) 5' AAGCGUUU 3' D) 5' AAGCGTTT 3'