Exam 4 Flashcards
Where is the light source diaphragm on the microscope
On the bottom, where light comes from
Where is the condenser diaphragm on a microscope
Under the stage
Where is the reostat on a microscope
It’s below the power button on the right
describe an agar plate
good for surface area. pure cultures
what are agar slants used for
storing cultures
what are agar deep’s good for?
showing if the organism is motile
What are CFU’s?
Colony forming units
in a standard plate count, what are you reading?
the colony forming units (CFU’s)
Is Mannitol salts selective, differential, or both?
both
If there is growth in Mannitol salts, what does that mean the organism can survive in?
in salt, (its a halodore)
when the pH goes down in Mannitol salts, what color will it turn?
yellow
Why would Mannitol salts turn yellow?
The mannitol fermented
Is MaConkey agar selective, differential, or both?
both
If bacteria grows in MaConkey agar, is it gram (+) or (-)
(-)
What does the MaConkey agar plate test for?
If lactose fermentation occurs
What color will the MaConkey agar turn if it ferments?
red/pink
what does the starch hydrolysis test test for?
if the organism can eat starch
what does the starch hydrolysis test use?
starch + iodine
if the starch hydrolysis plate clears up and has no color, what does that mean?
the bacteria CAN hydrolyze (eat starch)
is the starch hydrolysis plate differential, selective, or both?
differential
what does an oxidase test look for?
cytochrome C
what color will show is cytochrome C is present in the oxidase test? meaning it is oxidase positive
Blue
in a catalase test, what do you add?
hydrogen peroxide
is bubbles result in the catalase test, what does that mean?
it is catalase positive
the oxidase and catalase tests are both what kind of tests?
complex
mannitol salts test is selective for what
halodures (KEEP STUDYING!!!!)
mannitol salts test is differential for what?
mannitol fermentation
macConkey test is selective for what?
gram (-) growth
macConkey test is differential for what?
lactose fermentation
What test is tested on a blood plate?
hemolysis
if the blood agar turns green, what does that tell you? (2 things)
its Alpha (a) and it is incomplete hemolysis
if the blood agar turns clear, what does that tell you? (2 things)
complete lysis occured in the red cells of media, its Beta (b)
If the blood agar has no change, what does that tell you?
it’s gamma, no hemolysis
what do coloforms look like when they grow?
metallic green
When measuring a zone of inhibition, how is it measured?
in milimeters
do you want susceptibility in antibiotics?
yes
does alcohol kill spores?
no
what do gram stains the properties of?
the cell wall
what are the steps to a heat fix? (7 steps)
1) prepare the smear (loopful of water on slide, place bacteria and smear, let dry)
2) heat fix (over bunson burner x 3)
3) crystal violet (1 min)
4) Iodine (1 min)
5) alcohol (
what does heat fixing do to the bacteria? (3)
1) kills bacteria
2) adheres bacteria to slide
3) denatures proteins in membrane, making bacteria porous so state can penetrate
is gram positive or negative stained purple?
positive
what is epidemiology the study of?
where and when diseases occur and how they’re transmitted within populations
define incidence
the # of new cases of a disease in a given area or population during a given period of time
define prevalence
amount over time
define endemic
a natural occurrence in the area
define sporadic
occurring at irregular intervals
define epidemic
when a disease occurs more often than normal for an area
how far (over land) is an epidemic before it becomes a pandemic?
epidemics refer to 1 continent, not country
what is a pandemic
disease that spreads over more than 1 continent
what are 2 types of nosocomial infections?
exogenous
endogenous
latrogenic
what is an exogenous infection?
caused by pathogens acquired from healthcare environment
what is an endogenous infection?
they arise from normal microbiota in patient and become pathogenic because of factors in the health care setting
what are latrogenic infections
a direct result from a medical procedure. (use of catheters, surgery)
What is LD
lethal dose
what is ID
infectious dose
what are 3 contact transmission examples in infectious disease
direct, indirect, droplet
examples of direct transmission
handshaking, kissing, sexual intercourse
examples of indirect transmission
through an inanimate object
example of droplet transmission
sneezing
what are 3 vehicle transmissions for infectious disease?
airborne, waterborne, foodborne
what is an example of airborne transmission
dust particles
example of waterborne transmission
streams, pools
example of foodborne transmission
poultry, seafood, meat
what does vector mean in vector transmission of infectious disease
vectors are animals that transmit diseases from one hose to another.
what 2 things does vector transmission get broken down into?
mechanical and biologcial
whats (vector) mechanical transmission?
the animal did not bite you, but physically moved the disease to you. like a fly throwing up on us.
HI CHASE!
=)
whats (vector) biological transmission?
the animal bites. like lice, mites, mosquito’s, ticks
whats the first line of defense for our immune system?
mechanical (skin) and chemical (stomach-gastric juices)
whats the 2nd line of defense for our immune system?
all the physiological stuff
what makes up innate immunity?
the first 2 lines of defense
nonspecific defenses are also called what
innate
specific immunity is also called what?
adaptive
what is phagocytosis
(eating bacteria) ingestion of foreign particles by phagocytes
what are phagocytes
types of WBC or derivatives, aka leukocytes
what is in the outer membrane of ALL gram neg bacteria?
LPS
what are leukocytes?
white blood cells
what makes up the majority of WBC
neutrophils
what is the first cell type that reaches an injury?
neutrophils
are neutrophils powerful?
yes
can neutrophils phagocytose?
yes
what happens once neutrophils complete their jobs?
they die.
what do neutrophils do in regards to communications?
tells the rest of the system whats going on through cytokines
can eosinophils phagocytose?
NO CHASE THEY CANT!
what are eosinophils involved in?
eliminating parasites
can macrophages phagocytose?
YES
what do macrophages tell our immune system?
how to fight the infection
what are dendritic cells?
specialized macrophages
who do the dendritic cells talk to?
the specific immune system, specifically B & T cells
what is opsonization
process by which a pathogen is marked for ingestion and eliminated by a phagocyte
what do interferons work on and what do they do to them?
all virus’s, slow down genetics of the cell
inflammation is what kind of defense?
innate
what is inflammation (whats physically happening)
vasodialtion
what happens to your vessels when you have a fever
vasocontriction
what is fever caused by?
pyrogens!
what are 2 reasons your body generates a fever?
some pathogens don’t do well in heat
immune system works better in higher temps
what 2 things are associated with our primary immune system? (specific immunity)
bone marrow, thymus
what 2 things are associated with our secondary immune system? (specific immunity)
lymph nodes, spleen
what 3 roles do non-specific immunity play
- prevent infection
- contain infection until immunity can clear it
- present antigens (dendritic, machrtophages) to the specific immune system
what is our 3rd line of defense?
antigens
what are antigens?
a piece of the pathogen that the specific immune system can recognize
where do B lymphocytes arise and mature?
in bone marrow
what cell makes antibodies?
b cells
antibodies AKA
immunoglobulins
what are 4 functions of antibodies
- neutralize, prevent virus from doing anything
- opsonization, bind to bacteria and target it for phagocytosis
- agglutination, clumps the pathogen
- compliment, an antibody can kill bacteria directly
whats the first B cell made?
IgM
can IgM cross the placenta?
NOOOOO
what do IgM cells do?
starts compliment
what is the most abundant and soluble B cell?
IgG
which B cell do we not know the function of?
IgD
what to IgA cells do?
it goes into harsh environments and resists degradation
what do IgE cells do and what’s it related to?
binds to mast cells and related to allergies
where do T cells mature
thymus
what do T cells make?
antibodies
where are T cells made?
bone marrow
what do T cells release?
cytokines
how many antigens can the T cell receptor recognize?
just one, chase, just one!
what do helper T cells do? (2 things)
activate B cells and tell b cells which antibody to make
what do cytotoxic t cells do?
tell our cells to kill themselves (its infected)
in immunity memory, how long is the initial response?
7-14 days
in immunity memory, how long is the memory response?
2-6 days
which type of vaccine is best?
attenuated live vaccines
whats an inactivated vaccine?
dead virus, second best
what is a subunit vaccine
uses just a piece of the virus
what is a toxoid virus?
uses a piece of the toxin, chemically or thermally modified
what kind of disease is pertussis
bacterial
why are infants at risk for pertussis
their immunity isnt completely there yet
why dont we give the TB vaccine in america?
its expensive and then everyone would show positive and require a chest xray
endotoxins AKA
lipid A
what are 2 types of toxins?
endotoxins and exotoxins
what are fomites
inanimate objects that are inadvertently used to transfer pathogens to new hosts
examples of fomites (3)
needles, toothbrushes, medical equipment
what are reservoirs of infections
sites where pathogens are maintained
what are 3 types of reservoirs
animals, humans, and nonliving reservoirs
what is resident flora (4)
- permanent residence
- do not produce disease
- normal
- maintains balance
what is transient flora (3 plus one example)
- temporary
- not normally in the body
- not always bad
- like bacteria in yogurt
what is mutualism
both organisms benifit
what is commensalism
one organism benefits, the other is not effected
what is neutralism
not a true relationship
what is microbial antagonism
production of bacteriocides, what happens with normal flora
what is parasitism
one organisms benefits at the others expense
whats an example of a lichen
fungus, algae
what 4 sites are void of microorganisms naturally
- blood
- lymph
- spinal fluid
- internal tissues and organs