Micro - Chapter 9
Which is true regarding semiconservative DNA replication?
Each new DNA helix contains one parent strand and one newly synthesized strand
A point mutation results from an insertion or deletion of nucleotides, and always leads to a shift of the triplet sequence from the point of mutation downstream True or false
False
How many stop codons are contained within the genetic code?
3
All new DNA strands are synthesized from:
5' to 3'
Nucleotides can only be added to a growing DNA chain in the ______ direction
5' to 3'
The purine guanine pairs with the pyrimidine
Cytosine
Which type of mutation is generally most harmful to cells?
Frameshift mutation
During transcription, ______ is synthesized from a(n) ______ template
RNA; DNA
Which type of mutation is due to random mistakes in replication?
Spontaneous mutation
The three stop codons in the genetic code are
UAA, UAG, UGA
What site on a DNA molecule signals the end of a RNA transcript?
Termination
During which process is mRNA converted into a protein?
Translation
The specific sequence of three mRNA nucleotides that specify a particular amino acid is a(n) ___________ , or triplet
codon
Thymine and _________ are pyrimidines found in DNA
cytosine
A nucleotide is oriented 5' or 3' depending on the location of the Blank______ on the strand of DNA
deoxyribose carbons
DNA sequences found within a gene that do not encode the protein corresponding to the gene are
introns
An alteration in the DNA sequence of a cell is a(n)
mutation
A mutation that changes an amino-acid-producing codon into a stop codon, leading to premature termination of a protein, is a(n)
nonsense
The DNA strand that is not directly used for transcription into mRNA during protein synthesis is the ______ strand
nontemplate
In the cells of protozoa, fungi, animals, or plants, chromosomes are located in the
nucleus
A mutation that results from an insertion or deletion of a number of nucleotides that is not a multiple of 3, leading to a shift of the triplet sequence from the point of mutation downstream, is a(n)
frameshift
Mutations that are generally most harmful to cells because they cause the greatest change in the amino acid sequence of a protein are ____________ mutations
frameshift
The site on a chromosome where DNA replication begins is called the _______________ of replication
origin
The place where DNA replication is initiated is called the
origin of replication
Mutations that involve the addition, deletion, or substitution of one or a few bases are referred to as ______ mutations
point
The addition, deletion, or substitution of no more than a few bases as the result of a mutation is referred to as a(n) ___________ mutation
point
Some amino acids can be encoded by several different codons. For that reason, we say that the genetic code is
redundant
The enzymes responsible for building the DNA strand, proofreading newly produced DNA strands, and removing the RNA primer are DNA ___________________ I and III
polymerase
To initiate transcription, RNA polymerase binds to the ____________ region of DNA
promoter
DNA polymerases are responsible for
proofreading/repair, building the DNA chain.
The newly made double helices are composed of one parent template and one newly synthesized strand as a result of ______ replication
semiconservative
The newly made double helices are composed of one parent template and one newly synthesized strand as a result of ___________ replication
semiconservative
Two subunits of the ___________ come together to perform protein synthesis
ribosome
Mutations in DNA that are caused by random mistakes in replication, and are not known to be the result of any mutagenic agent, are ____________ mutations
spontaneous
The __________ codon AUG of mRNA is associated with the tRNA anticodon UAC and the amino acid methionine
start
The mRNA sequence AUG, specifying the first amino acid in protein sequences, is called the ____________ codon
start
The order of nucleotides that are transcribed into RNA is contained in the ______ strand of DNA
template
The end of an RNA transcript is signaled by a site on a DNA molecule called the _______________ site
termination
The end of an RNA transcript is signaled by a site on a DNA molecule called the ________________ site
termination
Cells that carry nonmutated DNA are called the ____________ type strain
wild
The native or ______ type strain exhibits nonmutated characteristics
wild
The carcinogenic potential of a chemical can be determined by the ______________ test
Ames
Which component of DNA determines the 3' and 5' ends of the strands?
Carbons in the deoxyribose sugar
The "blueprint" information for the production of proteins is encoded and stored in sections of
DNA
The genome of a cell is entirely composed of
DNA
Which best describes the flow of genetic information in a cell?
DNA encodes RNA which encodes protein
What determines the order of amino acids in the primary structure of a protein?
DNA sequence of a gene
Where are the chromosomes of eukaryotic cells located?
In the nucleus
Which DNA sequences are found within a gene but do not encode the protein specified by that gene?
Introns
Which type of mutation results in a different amino acid being incorporated into a protein?
Missense
Which mutation changes an amino acid-producing codon into a stop codon?
Nonsense
The genome of a prokaryotic or eukaryotic cell includes DNA found in which sites?
Plasmids, Chloroplasts, Mitochondria, Chromosomes
RNA polymerase binds to which region of DNA to begin transcription?
Promoter
The DNA blueprint specifies how to make what type of macromolecule?
Proteins
The main enzyme responsible for transcription is:
RNA polymerase
Which of the following are functions of RNA polymerase?
Synthesizes an RNA molecule from DNA template, Unwinds the DNA so that transcription can take place
What is the purpose of the Ames test?
To determine the carcinogenic potential of a chemical
A mutation is an alteration in the DNA sequence or content of a cell that is passed on when the cell divides True or false
True
Several codons can code for the same amino acid, which is called the redundancy of the code True or false
True
An mRNA codon is complementary to the ___________ region of a specific tRNA molecule
anticodon
The portion of tRNA that is complementary to the mRNA codon is the
anticodon
A mutation that results in a different amino acid being incorporated into a protein, with varying results, is a(n) __________ mutation
missense
A DNA nucleotide is composed of
one nitrogen base, deoxyribose sugar, and a phosphate group
Which type of RNA comprises ribosomal subunits?
rRNA
The process of decoding DNA into messenger RNA is
transcription
The information in mRNA is used to produce a protein during
translation
