Final Exam Flashcards
define bactericidal
kills microbes directly
define antibiotic resistance
when germs no longer respond to the drugs designed to kill them
what are broad spectrum antibiotics
antibiotics that effect a broad range of Gram+ and Gram- bacteria
what are narrow spectrum antibiotics
antibiotics that effect a range of bacteria (ex: affect Gram+ but few Gram-)
define sensitivity
the probability that the test is reactive if the specimen is a true positive
explain subunit vaccines
they use antigenic fragments of a microbe
what are monoclonal antibodies
(Mabs), antibodies produced by a single clone of cells or cell line and consisting of identical antibody molecules
what is a hybridoma
“immortal” cancerous B cell fused with an antibody-producing normal B cell, produces monoclonal antibodies
what is ELISA
(Enzyme-Linked Immunosorbent Assay), it is a test to see if patients’ sample has antigen and the enzyme linked to antibody is the indicator
define bacteriostatic
to prevent microbes from growing
define antibiotic
a substance produced by a microbe that, in small amounts, inhibits another microbe
what is selective toxicity
the killing of harmful microbes without damaging the host
what is an adjuvant
a substance that is added to a vaccine to increase the body’s immune response to the vaccine (aluminum salts improved vaccine effectiveness)
Penicillin was considered a “miracle drug” for what reasons?
Syphilis during WWII; It doesn’t affect eukaryotic cells, it inhibits gram-positive cell wall synthesis, it has selective toxicity, and it kills bacteria
Commercially available antimicrobial agents (i.e., antibiotics) are effective against what?
Killing or slowing the spread of microorganisms
The antibiotic tetracycline binds to the 30S subunit of the ribosome and this does what?
It blocks the binding of the aminoacyl-tRNA to the acceptor site on the mRNA-ribosome complex
The antibiotic cycloheximide binds to the 50S subunit of the ribosome and this does what?
It prevents the translocation of peptidyl-tRNA in the ribosome from site A to P
What does a zone of inhibition tell you about the effectiveness of an antibiotic?
a larger zone of inhibition usually means that the antimicrobial is more potent
Niclosamide prevents ATP generation in mitochondria. You would expect this drug to be effective against what?
helminths
The antibiotic actinomycin D binds between adjacent G-C pairs, thus interfering with what?
transcription
Rifamycin is an antibiotic that inhibits RNA synthesis which is what type or mode of action?
Polymerase (PCR?)
Antiviral drugs that effectively block the release of viral progeny from the infected cell(s) are compounds that do what?
Enable the progeny virions to leave the infected cells and spread to other host cells; they block receptors so viruses can’t bind to and enter healthy cells
Antiviral compounds that target the cell’s receptors often are referred to as what?
Antiviral drugs
The path of light through the compound microscope
illuminator, condenser, specimen, objective lens, ocular lens
the steps of the Gram stain
primary stain (crystal violet), mordant (Gram’s iodine), decolorizer (ethanol, acetone), counterstain (safranin)
what is streptococci
Gram+ coccus, spherical bacteria
what is a tetrad
a group or set of 4
name the prokaryotic cell cellular components
cell wall, cell membrane, capsule, pili, flagella, ribosomes, plasmids
what is simple staining
directly staining the bacterial cell with a positively charged dye in order see bacterial detail
define transformation
the process by which foreign DNA is introduced into a cell
define transcription
the process by which DNA is copied to RNA
define translation
when the transcribed RNA is used to make proteins
what is the expected growth pattern for an obligate anaerobe
growth only on bottom
what is the expected growth pattern for an obligate aerobe
growth only on top
what is an endemic disease
a disease spreading in a particular population, environment, or region at the normal or expected level
define PCR
(polymerase chain reaction), a laboratory technique for rapidly producing or amplifying millions to billions of copies of a specific segment of DNA
what is a DNA probe
a single-stranded sequence of DNA or RNA used to search for its complementary sequence in a sample genome
define microbe
an organism that can only be seen through a microscope
define pathogen
a microorganism that causes, or can cause, a disease
define IgM
the largest and first antibody produced by the immune system when a virus attack’s
define agar
an aseptic and solidifying component used as a culture medium for growing microorganisms
what is innate immunity
the first line of defense against invading pathogens; the defense system with which you were born (nonspecific immunity)
what are nosocomial infections
infections patients acquire while admitted to a health-care facility (aka hospital-acquired infection or health-care associated infection)
That life forms can arise spontaneously (“pop up”) from non-living matter is referred to as what?
Spontaneous generation
Which structure acts like an “invisibility cloak” and protects bacteria from being phagocytized?
capsule
What are the necessary components for DNA synthesis and protein synthesis to occur?
substrates, template, primer, and enzymes
Genetic change in bacteria can be brought about by what processes?
transformation, conjugation, transduction, and mutation
Which terms or phrases are a necessary component for bacterial conjugation?
direct contact between donor and recipient cells, shortening of the pilus, enzymatic cleavage of one strand at the origin of transfer, recipient cell becomes a donor cell after conjugation
Recombinant DNA technology is used for what in our lives?
To make important proteins used in the treatment of human diseases, such as insulin and growth hormone
What is the mechanism whereby an enveloped virus leaves a host cell called?
budding
Who is the physician first associated with vaccination?
Edward Jenner
In the scientific name Staphylococcus aureus, the word aureus is what part of the name?
species
During DNA synthesis, if a base on the template strand is cytosine (C), what is the base that will be added to the growing or complimentary strand?
guanine (G)
What techniques (or procedure) achieve sterilization?
wet heat (autoclaving: high pressure is applied with a recommended temp of 250F for 15-20 minutes, dry heat (baking or flaming), filtration, chemicals/solvents, radiation
The genetic code is said to be degenerate. Degeneracy in the genetic code means what?
it is a phenomenon in which several of the amino acids are each coded by more than one codon
The specificity of an antibody is due to what?
the unique antigen binding site located at the tip of the variable region on the antibody
