Microbiology Mcgraw hill chp 9, 10, 11, 12
DNA polymerases are responsible for
- proofreading/repair - building the DNA chain
A codon contains how many nucleotides?
3
Approximately how many base pairs are found in the human genome?
6.4 billion
Approximately what percent of infections involve biofilms?
60%
The temperatures (in degrees Celsius) used in incineration must usually be above which of the following?
800
Which piece of equipment in the microbiology lab uses incineration to minimize contamination?
Bunsen burner
During transcription, _____ is synthesized from a(n) ______ template.
RNA, DNA
Which of the following vegetative bacterial cells is more resistant to moist heat?
Staphylococcus aureus
A(n) _____ is a sterilization chamber that allows the use of steam under pressure to sterilize materials.
autoclave
Which of the following is the biggest disadvantage of using boiling water for disinfection?
The quick recontamination of items
Which "formation" is produced by some microbes which in turn makes them resistant to some antimicrobial compounds and the shear force of moving liquids?
biofilm
Which describes the spectrum of activity of the tetracyclines?
broad
A discrete cellular structure composed of a neatly packaged DNA molecule is a(n)
chromosome
The specific sequence of three mRNA nucleotides that specify a particular amino acid is a(n) _______, or triplet.
codon
The tolerance of an antimicrobial agent at a level which would normally be inhibitory is called which of the following?
drug resistance
Gel electrophoresis is a laboratory technique for separating DNA fragments according to length by employing _______ to cause the DNA to move through a gel-like matrix.
electricity or current
A laboratory technique for separating DNA fragments according to length by employing electricity to force the DNA through a gel-like matrix is gel _____
electrophoresis
Enzymes that break phosphodiester bonds at specific locations on DNA are called ______ enzymes.
endonuclease
Which enzyme cleaves specific locations on DNA to produce fragments that are used to splice genes in genetic engineering?
endonuclease
In eukaryotes, which DNA sequences encode functional protein?
exons
Within a gene, the DNA sequences that encode the functional protein are called
exons
Most vegetative forms of microorganisms are susceptible to the same exposure to heat.
false
Which DNA sequences are found within a gene but do not encode the protein specified by that gene?
introns
An alteration in the DNA sequence of a cell is a(n)
mutation
The outer membrane of some Gram- _______ bacteria acts as a natural barrier to some drugs.
negative
A segment of DNA that codes for protein or RNA is a(n) __.
gene
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
The entire genetic makeup of an organism is the ______, but the expression of certain genetic traits is known as the ______.
genotype; phenotype
DNA that has been separated into its two strands when the temperature is increased is called _______-_______ DNA.
heat-denatured
The enzymes responsible for building the DNA strand, proofreading newly produced DNA strands, and removing the RNA primer are DNA ________ I and III.
polymerase
The tetracyclines bind to which of the following structures?
ribosomes
Heat-denatured DNA is the term used to describe DNA that has been separated into two strands when the ______ is increased.
temperature/heat
A mutation is an alteration in the DNA sequence or content of a cell that is passed on when the cell divides.
true
Cells that carry nonmutated DNA are called the _______ type strain.
wild
Which of the following are the least resistant to moist and dry heat?
- Vegetative states of fungi - Vegetative states of bacteria
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 are the effects of adding pressure to water in an autoclave?
- Increases boiling point of water - Increases temperature of steam
Eukaryotic chromosomes are composed of
DNA
Genes are specific segments of
DNA
DNA sequences found within a gene that do not encode the protein corresponding to the gene are
Introns
The main enzyme responsible for transcription is:
RNA polymerase
Which of the following describes the primary structure of a protein?
The chain of amino acids
Using PCR, over a short period of time, the amount of DNA in a sample ______
increases
Lower temperatures for shorter times are characteristic of _____ heat, while ____ heat requires higher temps and longer exposure times for the same effectiveness.
moist, dry
The specific order of amino acids bound to each other by peptide bonds represents the _______ structure of a protein.
primary
The process of decoding DNA into messenger RNA is
transcription
During which process is mRNA converted into a protein?
translation
