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