Microbiology: Exam 2
In eukaryotes, coding regions of DNA that will be translated into protein are called_________
Exons
T/F: ATP is composed of deoxyribose, adenine, and three phosphate groups.
F. Ribose Sugar and adenine ring, and three phosphate group
The movement of substances from higher to lower concentration across a semipermeable membrane that must have a specific protein carrier but no energy expenditure is called
Facilitated Diffusion
An organism that can exist in both oxygen and oxygen-free environments is a/n
Facultative Anaerobe
An organism that grows slowly in the cold but has an optimum growth temperature of 32° C is called a/n
Facultative Psychrophile
In bacterial cells, when glucose is completely oxidized by all the pathways of aerobic cellular respiration, what is the maximum number of ATP generated
38
Length of a typical tRNA molecule?
75-95 bases
Sulfonamides and Trimethoprim
Folic Acid Synthesis Inhibitors
T/F: Viral genomes are always composed of either single or double stranded DNA.
False. Include RNA
The duplication of a cell's DNA is called
Replication
The first three RNA nucleotides that signal the beginning of the message. The start codon is always AUG
Start Codon
The phase of the bacterial growth curve in which the rate of multiplication equals the rate of cell death is the
Stationary Phase
Mechanism of Resistance: Drug is immediately eliminated (occurs through the acquisition of new genes)
Stealth Mode
________________radiation excites atoms to a higher energy state within molecules such as DNA that then leads to the formation of pyrimidine dimers.
Ultraviolet
During replication, each parent DNA strand serves as a _____ for synthesis of new DNA strands.
Template
Groups of three consecutive bases along the DNA of a gene have the code for one:
amino acid.
What kind of RNA carries or brings the amino acids to the ribosomes?
Transfer RNA
RNA molecules is then used to produce proteins in a process known as
Translation
__________________________is the synthesis of proteins using RNA as a template.
Translation
Mechanism of Resistance: Binding sites for drugs are decreased in number and or affinity (occurs via mutation or through the acquisition of new genes) Pt 2 An Affected metabolic pathway is shut down or an alternative pathway is used (occurs via mutation or through the acquisition of new genes)
Up-Chuck
T/F: During protein synthesis, many copies of a specific protein can be synthesized from a single mRNA transcript
True
T/F: Hydrolysis reactions are catabolic reactions that use water to split the reactant into smaller subunits.
True
T/F: · Several codons code for the same amino acid which is called the redundancy of the code
True
· DNA from one parent organisms during reproduction.
Vertical Gene Transfer:
Main event of translation initiation mRNA ________________
binds to the ribosome
New enzymes are synthesized, inactivating the drug ( occurs through the acquisition of new genes))
Mechanism of Resistance
A permanent, inheritable change in the genetic information is called a/n
Mutation
Diffusion of water through a semipermeable membrane is called:
Osmosis
The most likely place where an exoenzyme participates in a chemical reaction is
Outside of the cell
In bacterial cells, the electron transport system is located in the:
cell membrane
Molecules called ____________________________ · can be made from messenger, transfer, ribosomal, and other forms of RNA.
complementary DNA (cDNA)
The pyrimidine nitrogenous bases found in DNA are
cytosine and thymine.
The movement of molecules from an area of high concentration to an area of lower concentration is called
diffusion
Surfactants work by
disrupting membrane integrity
Bacterial conjugation involves
donor cell with a plasmid that synthesizes a pilus.
The term obligate refers to
existing in a very narrow niche.
Full induction of the lactose operon requires
lactose present without glucose.
Another enzyme __________ is necessary to seal the sticky ends together by rejoining the phosphate-sugar bonds cut by endonucleases
ligase
The term used to describe all of the chemical reactions within a cell is:
metabolism
A permanent, inheritable change in the genetic information is called a/n:
mutation.
Each of the following is a mechanism for drug resistance transfer between microorganisms except
mutation.
The ________________ · DNA strand is the strand that is not directly used for transcription into mRNA during protein synthesis.
non-template
Electrons are ejected from atoms in cells when organisms are exposed to
gamma rays and X rays.
A technique that separates a readable pattern of DNA fragments is:
gel electrophoresis
A _____ is a specific segment of DNA that codes for the production of one functional product:
gene
short stretch of DNA of a known sequence that will base-pair with a stretch of DNA with a complementary sequence, if one exists in the test sample.
gene probes
Labeled, known, short stretches of DNA used to detect a specific sequence of nucleotides in a mixture are known as
gene probes.
Genetically modified organisms include:
o All of the above have been genetically modified. Bacteria o Viruses o Plants o nonhuman animals
Correct statements regarding eukaryotic transcription are correct?
o Transcription occurs before splicing. o The exon-intron junction is recognized by a spliceosome.
An organism that cannot tolerate an oxygen environment is a/n
obligate anaerobe.
All of the following pertain to transcription except
occurs on a ribosome in the cytoplasm
All of the following pertain to nitrogenous bases except:
guanine pairs with uracil.
The term facultative refers to
he ability to exist in a wide range of conditions.
The first genetically engineered protein approved for human use was:
human insulin.
Two different nucleic acids can _____ by uniting at their complementary sites:
hybridize
As the electron transport carriers shuttle electrons, they actively pump _____ into the outer membrane compartment, setting up a concentration gradient called the proton motive force.
hydrogen ions
Physical agents for controlling microbial growth include all of the following except
hydrogen peroxide.
Enzymes that catalyze the removal of electrons from one substrate and the addition of electrons to another are called
oxidoreductases.
During aerobic cellular respiration, the final electron acceptor is
oxygen.
An organism that uses CO2 for its carbon needs and sunlight for its energy needs would be called a
photoautotroph
versatile way to amplify DNA
polymerase chain reaction (PCR) -· technique rapidly increases the amount of DNA in a sample without the need for making cultures or carrying out complex purification techniques.
Amplification of DNA is accomplished by:
polymerase chain reaction.
RNA polymerase binds to the ____________ · to initiate transcription.
promoter region
_______ and ________ compose ribosome subunits.
rRNA and protein
The deliberate removal of genetic material from one organism and its subsequent transfer into the genome of another organism is a specific technique called
recombinant DNA technology
The pieces of DNA produced by restriction endonucleases are termed
restriction fragments.
The ___________ is a particle composed of two subunits of rRNA that is the site of protein synthesis.
ribosome
A halophile would grow best in:
salt lakes
Broad-spectrum drugs that disrupt the body's normal biota often cause
superinfections.
The term facultative refers to:
the ability to exist in a wide range of conditions
Antibiotic rifamycin can be used to treat tuberculosis because
the drug is more active against bacterial RNA polymerase than the human enzyme.
Helicase
unwinds DNA
This property, called ________ is thought to permit some variation or mutation without altering the message
wobble
Main event of translation termination?
· A nonsense codon is reached and the peptide is released from the ribosome.
is the formation of RNA using DNA as a template.
Transcription
DNA vs RNA
-RNA contains uracil (U) -backbone that consists of alternating sugar (ribose) -It is a single-stranded molecule that exists in helical form
The movement of substances from lower to higher concentration across a semipermeable membrane that must have a specific protein carrier and cell expenditure of energy is called:
Active transport
Which PCR step synthesizes complementary DNA strands?
Add DNA polymerase and nucleotides at 72° C.
· Transposable elements are capable of moving from
All TEs share the general characteristic of traveling from one location to another on the genome—from one chromosomal site to another, from a chromosome to a plasmid, or from a plasmid to a chromosome
Analysis of DNA fragments in gel electrophoresis is based on
All of the choices are correct. - Larger fragments moving slowly and remaining closer to the wells. - DNA having an overall negative charge and moving to the positive pole. - DNA fragments being stained so that they can be seen. - Application of an electric current through the gel causing DNA fragments to migrate.
Analysis of DNA fragments in gel electrophoresis is based on:
All of the choices are correct. -larger fragments moving slowly and remaining closer to the wells, - DNA having an overall negative charge and moving to the positive pole, - DNA fragments being stained so that they can be seen, application of an electric current through the gel causing DNA fragments to migrate)
Groups of three consecutive bases along the DNA of a gene have the code for one
Amino acids
Formation of peptide bonds between amino acids to build a polypeptide would be called
Anabolism
Mechanism of Resistance: Permeability or uptake of the drug into the bacterium is decreased (occurs via mutation)
Ballistic Missile Defense
Opposite Sequence: The anticodon of the tRNA carrying the codon GUU=
CAA
Penicillins Cephalosporins Bacitracin Vancomycin
Cell Wall Inhibitors
Polymyxins
Cell membrane Inhibitors
What is the central dogma hypothesis of genetics?
DNA encodes RNA encodes protein.
Why is an enzyme from a thermophilic bacterium used in PCR?
DNA is replicated at a high temperature that denatures most proteins.
In the formation of recombinant DNA, what enzyme is needed to seal the sticky ends of genes into plasmids or chromosomes?
DNA ligase
A retrotransposon can transcribe______ into ______ and then back into DNA for insertion in a new genomic location
DNA, RNA
DNA from a source other than the parent organisms.
Horizontal Gene Transfer:
Base pairs in DNA are held together by _____ bonds.
Hydrogen
____________are DNA sequences found within a gene that do not encode the protein corresponding to the gene
Introns
Fluoroquinolones Rifampin
Nucleic Acid Inhibitors
What are areas of the genome where multiple genes exist that are coordinated to give a new trait and make the bacteria more pathogenic
Pathogenicity islands.
Antibiotic tha does NOT target transcription or translation in bacteria?
Penicillin
Which process in bacteria do the antibiotics tetracycline,chloramphenicol and erythromycin specifically inhibit?
Protein Synthesis
Erythromycin Clindamycin Aminoglycosides Tetracyclines
Protein Synthesis Inhibitors
Primaquine and chloroquine are drugs used in the treatment of ___ infections.
Protozoan
During Transcription RNA polymerase synthesizes _____ and _______template.
RNA and DNA template
Gene regulation can involve a protein repressor that blocks ..... from initiating transcription.
RNA polymerase
The antibiotic rifamycin, used to treat tuberculosis, binds and inhibits the activity of
RNA polymerase
· Which of the following is the genetic pattern of viral genomes?
Single or double stranded DNA or RNA
gel electrophoresis
The separation of nucleic acids or proteins, on the basis of their size and electrical charge, by measuring their rate of movement through an electrical field in a gel. -· give the entire molecule an overall negative charge, which causes the DNA to move toward the positive pole in the gel
Reverse transcriptase is used to make cDNA from an RNA template.
True
The cellular basis for bacterial resistance to antimicrobials include
a. All of the choices are correct. - bacterial chromosomal mutations. - synthesis of enzymes that alter drug structure. - prevention of drug entry into the cell. - alteration of drug receptors on cell targets.
Alcohols
a. All of the choices are correct. -denature proteins when in a 50-95% alcohol-water solution. -disinfect items when soaking method is utilized. -are skin degerming agents. -at 50% or higher concentrations dissolve cell membrane lipids.
Semiconservative replication refers to:
an original parent DNA strand and one newly synthesized DNA strand comprising a new DNA molecule.
semiconservative replication refers to
an original parent DNA strand and one newly synthesized DNA strand comprising a new DNA molecule.
The alcohol wipe used on a patient's skin before an injection is an example of
antisepsis.
The bacterial genus Bacillus can utilize starch as a nutrient by splitting the starch molecule into smaller molecules of glucose, with the addition of water. The enzymes to do this would be classified as:
hydrolases.
Enzymes are:
proteins that function as catalysts
Enzymes are
proteins that function as catalysts.
All of the following could find a location in or on body tissues suitable for growth except
psychrophiles
During _____________________RNA polymerase synthesizes a strand of mRNA from template DNA.
transcription elongation
The process of ______________________· results in the release of a completed RNA transcript.
transcription termination
The RNA molecules that carry amino acids to the ribosomes during protein synthesis are called
transfer RNA
The transfer of DNA fragments from a dead cell to a live, competent recipient cell that results in a changed recipient cell is termed
transformation.