Ch. 9 Smartbook--An Introduction to Microbial Genetics
The DNA of a chromosome is ________ -stranded.
Double
What type of DNA mutation occurs as a consequence of exposure to chemical or physical mutagens?
Induced
Which is the correct order of events in transcription, starting with the first event at the top? Instructions Initiation Termination Elongation
Initiation Elongation Termination
The first three events of translation in the correct order are ______________, ____________, ______________ followed by protein folding and processing.
Initiation Elongation Termination
Which is the correct order of events when a protein is made in the process of translation, starting with the first event?
Initiation, elongation, termination
A mutation that results in a different amino acid being incorporated into a protein, with varying results, is a(n) __________ mutation.
Missense
Which type of mutation results in a different amino acid being incorporated into a protein?
Missense
How does RNA differ from DNA?
RNA is single-stranded. In RNA, uracil replaces thymine.
During transcription, ______ is synthesized from a(n) ______ template.
RNA; DNA
Which term refers to the transfer of genes from donor to recipient microorganisms?
Recombination
The newly made double helices are composed of one parent template and one newly synthesized strand as a result of _________ replication.
Semiconservative
Which of the following is the genetic pattern of viral genomes?
Single or double stranded DNA or RNA
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
Which type of mutation is due to random mistakes in replication?
Spontaneous mutation
Which of the following describes the primary structure of a protein?
The chain of amino acids
What is a true statement about the replication of cells and viruses? 1. The general process of replication is similar in cells and viruses. 2. The general process of replication is similar in prokaryotic and eukaryotic cells, but viruses differ significantly. 3. The general process of replication of prokaryotic cells is not similar to eukaryotic cells or viruses.
The general process of replication is similar in cells and viruses.
The process of decoding DNA into messenger RNA is ____________.
Transcription
During which process is mRNA converted into a protein?
Translation
The information in mRNA is used to produce a protein during _________.
Translation
Which term, synonymous with codon, describes a trinucleotide sequence coding an amino acid in DNA?
Triplet
A mutation is an alteration in the DNA sequence or content of a cell that is passed on when the cell divides.
True
Unlike DNA, RNA contains the nitrogenous base ____________.
Uracil
Select all that apply Which of the following are physical, as opposed to chemical, agents that can cause mutations? Multiple select question. X-rays Acridine dyes Ethidium bromide Nitrous acid Ultraviolet light
X-rays Ultraviolet light
Methicillin-resistant Staphylococcus aureus (MRSA) strain produces vancomycin resistant enterococci (VRE) with the gene transfer of _________.
a transposon containing the vanA operon
A sex pilus functions in most transfers of genes between bacteria that are known as _____________.
conjugation
One DNA repair mechanism that removes incorrect bases, and replaces them with correct ones, is the ______ repair mechanism.
excision
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
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
A segment of DNA that codes for protein or RNA is a(n) __________.
gene
There are 4,288 ___________ in the chromosome of Escherichia coli.
genes
There are 4,288 _____________ in the chromosome of Escherichia coli.
genes
The science of heredity is also known as _________.
genetics
The study of the inheritance in living things is __________.
genetics
During eukaryotic protein synthesis, ______ ribosome(s) is (are) used to translate mRNA that contains ______ gene(s).
many, one
Which is an agent that induces changes in DNA?
mutagen
An alteration in the DNA sequence of a cell is a(n) ___________.
mutation
A small number of _____________ are considered beneficial in that they provide the cell with a useful change in structure or physiology.
mutations
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
The specific order of amino acids bound to each other by peptide bonds represents the ___________ structure of a protein.
primary
The main effect of ultraviolet radiation on DNA is abnormal bonding between adjacent _________.
pyrimidines
When one bacterium donates DNA to other bacterium, it is known as _________.
recombination
When one bacterium donates DNA to other bacterium, it is known as __________.
recombination
The information in mRNA is used to produce a protein during __________.
translation
"Jumping genes" are known as _________.
transposons
Genes that are able to shift from one part of the genome to another are _____.
transposons
Genes that are able to shift from one part of the genome to another are _______.
transposons
The term __________ , or codon, is a sequence of 3 nucleotides in DNA that encodes an amino acid.
triplet
Vancomycin-resistant enterococci (VRE) arise when, through genetic transfer, a MRSA strain acquires the ________ operon located within a ___________.
vanA transposon
In a chromosome, the DNA is composed of ______ strands.
2
The 46 human chromosomes contain approximately ______ times as many genes compared to the single chromosome of E. coli.
5
Select all that apply Which of the following are caused by chemical mutagens? Multiple select question. Base substitutions Frameshift mutations Thymine dimers Double stranded breaks
Base substitutions Frameshift mutations
What is the main effect of ultraviolet radiation on DNA?
Abnormal bonding between adjacent pyrimidines
Select all that apply Which of the following are chemicals that can cause mutations? Multiple select question. Acridine dyes Ultraviolet light X-rays Ethidium bromide Nitrous acid
Acridine dyes Ethidium bromide Nitrous acid
Which type of RNA is transcribed from a DNA template?
All types of RNA
A discrete cellular structure composed of a neatly packaged DNA molecule is a(n) __________.
Chromosome
Eukaryotic chromosomes are composed of ___________.
DNA
Genes are specific segments of _____________.
DNA
The flow of genetic information in a cell is a process starting with ________ which encodes ________ which encodes protein.
DNA RNA
Which best describes the flow of genetic information in a cell?
DNA encodes RNA which encodes protein
Which is true regarding semiconservative DNA replication?
Each new DNA helix contains one parent strand and one newly synthesized strand.
Transcription involves initiation, _________, and termination.
Elongation
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.
False
Mutations are always harmful to cells.
False
The process of replication is fundamentally different in prokaryotic cells, eukaryotic cells, and viruses.
False
The ways that tRNA, rRNA, and mRNA are synthesized are very different from one another.
False
Viral genomes are always composed of either single or double stranded DNA.
False
Which of the following are caused by chemical mutagens?
Frameshift mutations Base substitutions
The complete set of chromosomes and genes in an organism is referred to as the _________.
Genome
Which term represents all of the genetic information within a cell?
Genome
An agent that induces changes in DNA is a(n) ___________.
Mutagen
A mutation that changes an amino-acid-producing codon into a stop codon, leading to premature termination of a protein, is a(n) _________.
Nonsense
Which mutation changes an amino acid-producing codon into a stop codon?
Nonsense
Viral initiators of cancer are termed __________.
Oncogenic
Select all that apply: Which of the following are parts of a nucleotide in DNA? Multiple select question: Ribose sugar Phosphate Deoxyribose sugar Nitrogenous base Amino acid
Phosphate Deoxyribose Nitrogenous
Which process uses visible light to repair DNA that has been damaged by ultraviolet radiation?
Photoactivation
Donor and recipient bacterial cells are connected by the sex __________ during conjugation.
Pilus
What is a small circular segment of DNA found in the cytoplasm of prokaryotes that is capable of independent replication and usually contains nonessential genes?
Plasmid
Select all that apply Exposure to chemical mutagens can lead to mutations because chemical mutagens can cause: Multiple select question. inappropriate base pairing during DNA replication. insertions and deletions during DNA replication. formation of thymine dimers. insertion of a transposon sequence into a gene. double-stranded breaks in DNA.
inappropriate base pairing during DNA replication. insertions and deletions during DNA replication.
Any alteration in DNA that occurs as a consequence of exposure to chemical or physical mutagens is a(n) ____________ mutation.
induced
In protein synthesis, eukaryotic and prokaryotic cells show similarities in all of the following EXCEPT the:In protein synthesis, eukaryotic and prokaryotic cells show similarities in all of the following EXCEPT the: Multiple select question. operation of ribosomes. mass production of proteins using polyribosomes. functions of start and stop codons. number of proteins encoded on a single mRNA. use of formyl-methionine as the first amino acid.
number of proteins encoded on a single mRNA. use of formyl-methionine as the first amino acid.
Several DNA viruses are known to be initiators of cancers and are thus termed ________.
oncogenic
A DNA nucleotide is composed of a(n) ______________, a(n) __________ sugar, and a(n) ___________ base.
phosphate deoxyribose nitrogenous
Donor and recipient bacterial cells are connected by the sex _________ during conjugation.
pilus
A small circular segment of DNA found in the cytoplasm of bacteria that is capable of independent replication and usually contains nonessential genes is a(n) _____________.
plasmid
Mutations that involve the addition, deletion, or substitution of one or a few bases are referred to as _________ mutations.
point