Microbiology: Exam 2 Study Module Ch 6, 9, 10
The ---- test is used to determine the carcinogenic potential of a chemical.
-Ames
Identify the different environments in which some viruses can replicate.
-Animal cells -Human cells -Bacterial cells
Any virus that specifically infects bacteria is called a(n) ------.
-Bacteriophage or Phage
Scientist who proposed term "virus"?
-Beijernick
At minimum, viruses are composed of which of the following?
-Capsid and Nucleic Acid
Which are the criteria used in classifying viruses into families?
-Chemical composition -Genetic makeup -Structure
---- in bacteria refers to horizontal gene transmission via pili.
-Conjugation
A ---- binds to an inactive repressor to make an active repressor.
-Corepressor
Similar to differentiating organisms based on their phenotypes, technology involving analysis of specific sequences of ---- can be used to differentiate between members of the same species.
-DNA
Which best describes the flow of genetic information in a cell?
-DNA encodes RNA which encodes protein
Which type of microscope is usually used to examine viruses?
-Electron
In eukaryotic cells, gene expression is regulated in response to ---- stimuli such as nutrient and toxin levels, and also during growth and ----
-Environmental -Development
Proteins that remove incorrect bases and replace them with correct ones are termed ______ repair enzymes.
-Excision
What is the name of the specialized plasmid that directs conjugation in gram-negative cells?
-F or Fertility Factor
True or false: Bacterial conjugation is a sexual process.
-False Bacteria have no exact equivalent to sexual reproduction, but use conjugation for gene exchange via pili.
True or false: Mutations are always harmful to cells.
-False Some mutations help cells survive, such as with mutations that lead to antibiotic resistance in bacteria.
True or false: Viral genomes are always composed of either single or double stranded DNA.
-False Viral genomes may be composed of single or double stranded DNA or RNA.
What process involves the introduction of normal functional genes into cells of people with genetic diseases such as sickle cell anemia and cystic fibrosis?
-Gene therapy
Using laboratory animals for experimentation is considered which of the following?
-In vivo
Which Latin phrase describes the cultivation or testing within a living organism or tissues?
-In vivo
DNA sequences found within a gene that do not encode the protein corresponding to the gene.
-Introns
Which 2 scientists are credited with discovering the tobacco mosaic virus?
-Ivanovski and Beijerinck
To eradicate the Aedes aegypti mosquito that spreads Zika virus, scientists in Brazil produced a mosquito with a ______ gene that causes death in offspring.
-Limiting
The discovery of the light microscope had what type of impact on the observation of viruses?
-Little to none
A permanent inheritable 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
A(n) ------ virus does not have an envelope surrounding its capsid.
-Naked
The mechanisms of ---- transformation involve genes that can regulate cellular genomes and control the onset of cell division.
-Oncogenic
Several DNA viruses are known to be initiators of cancers and are thus termed ----
-Oncogenic or Oncoviruses
Two components of an operon include the ---- that acts as an on/off switch, and the ---- gene sequences.
-Operator -Structural
Which of the following terms describes viruses in the carrier state within the host cells?
-Persistent infections
Which process repairs DNA that has been damaged by ultraviolet radiation using visible light?
-Photoactivation
A ---- is a small circular segment of DNA found in the cytoplasm of bacteria that is capable of independent replication and usually contains nonessential genes.
-Plasmid
Mutations that involve the addition, deletion or substitution of one or a few bases are referred to as _______ mutations.
-Point
DNA ---- is a forensic science tool that allows for the comparison of genomic patterns between individuals.
-Profiling
Prions are composed of what molecule?
-Protein
Viruses are composed of which of the following?
-Protein capsid -DNA or RNA
Which of the following best describes a prion?
-Proteinaceous-infectious agent
The main enzyme responsible for transcription is
-RNA polymerase
Which 3 of the following are usual choices for live animal inoculation with viruses?
-Rats -Hamsters -White mice
Large scale production and safer products are two of the advantages of using ---- products instead of natural products.
-Recombinant
The plasmid is not taken up by all cells in the culture when conducting cloning, or ---- DNA technology.
-Recombinant
---- refers to the transfer of genes from donor to recipient microorganisms, where the recipient strain shows a change in genetic makeup at the end.
-Recombination
Which term refers to the transfer of genes from donor to recipient microorganisms?
-Recombination
---- RNA may exert control on several levels in both prokaryotes and eukaryotes.
-Regulatory
The protein product of a repressor gene is the ---- which binds the operator to stop transcription.
-Repressor
The ---- protein is capable of repressing an operon.
-Repressor or Regulator
What are the advantages of using recombinant products instead of natural products?
-Safer products -Large-scale production
A persistent infection could last how long in a host?
-Several days, weeks, or years
Which of the following is the genetic pattern of viral genomes?
-Single or double stranded DNA or RNA
The plasmid is taken up by _____ cells in the culture when conducting recombinant DNA technology.
-Some
---- mutations in DNA are caused by random mistakes in replication and not known to be influenced by any mutagenic agent.
-Spontaneous
Which are components of an operon in a sequence of DNA?
-Structural genes -Operator
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
The cause of viral infections remained unknown for many years longer than other types of infections due to which reasons?
-Techniques used to observe other pathogens were useless with viruses -Viruses are not visualized by light microscopes
Which is not a reason that eggs provide an excellent in vivo viral cultivation system?
-The egg contains a tissue monolayer
DNA technology can be used to differentiate between members of ________ species.
-The same
Which of the following is considered an in vitro method for virus propagation?
-Tissue culture
A recombinant organism that carries foreign genes is called a ______ organism.
-Transgenic -Genetically modified
The term -----, or codon, is a sequence of 3 nucleotides in DNA that encodes an amino acid.
-Triplet
True or false: A mutation is an alteration in the DNA sequence or content of a cell that is passed on when the cell divides.
-True
True or false: DNA fingerprinting (also called DNA profiling) is a forensic science tool that allows for the comparison of genomic patterns between individuals.
-True DNA fingerprinting is the best known tool of forensic science.
Which bird eggs are the most common choices for viral propagation?
-Turkey -Duck -Chicken
Which term best describes viruses?
-Ultramicroscopic
Which one is a genetic element such as a plasmid or virus used to introduce DNA into a cloning host during recombinant DNA experiments?
-Vector
Which of the following enables some viruses to propagate better in a particular animal compared to others?
-Virus-specific animal receptors
List the correct order of viral life cycle phases, placing the first phase at the top.
1. Adsorption 2. Penetration/Uncoating 3. Synthesis 4. Assembly 5. Release
The first three events of translation in the correct order are ---, ---, --- followed by protein folding and processing.
1. Initiation 2. Elongation (chain elongation) 3. Termination
The three types of RNA are
1. Messenger (mRNA) 2. Transfer (tRNA) 3. Ribosomal (rRNA)
