Midterm #1 Flashcards
where is DNA located within a prokaryotic cell
located within the nucleoid
how large are prokaryotic ribosomes and how large are the subunits
P ribosomes are are 70s and composed of 30s subunit and 50s subunit
in eukaryotic cells what is the site of rRNA synthesis and pre ribosomal assembly
the nucleolus
how large are ribosomes in eukaryotic cells and how large are the subunits
E ribosomes are 80s and composed of a 40s subunit and 60s subunit
what kind of proteins do free ribosomes produce
water soluble proteins
what kind of proteins do membrane ribosomes produce
they make proteins that are inserted into the cell membrane or exported from the cell
what is the function of the SER
-production of lipids
-carb metabolism
-removes toxic compounds from the cell
What is the function of the RER
transports proteins to
-the golgi apparatus
-directly to the plasma membrane
-other organelles
-outside the cell
what are the three components of the cytoskeleton
-Microfilaments
-intermediate filaments
-Microtubules
what is the nuclear lamina composed of
composed of intermediate filaments
what are desmosomes composed of
intermediate filaments
what are flagella and cilia composed of
microtubules
what shape is a coccus
round ball
what shape is a bacillus
A rod
What shape is a Vibrio
curved rod
what shape is a coccobacillus
a squished rod
what shape is a spirilla
spiral
what shape is a spirochete
a longer looser spiral
what does the prefix Strepto- mean?
strepto is a chain of cells (remember Srepto sounds like street which is a straight like a chain)
what does the prefix staphylo- mean
a cluster of cells (remember staphylo- sounds like staff so think of a staff huddle like a cluster)
What is a cell capsule
an extra envelope that that wraps around the cell that can make the cell harder to kill and adhere better which increases its pathogenicity
what is an outer membrane
a second lipid bilayer that is found on the outside of gram negative bacteria that has LPS attached to it
what kind of cell contains a thick layer of peptidoglycan
Gram positive
what kind of cell has a thinner layer of peptidoglycan
gram negative bacteria
what color are gram negative cells after a test
gram negative cells appear pink
what color are gram positive cells after a test
they appear purple
what are 2 important characteristics of gram positive cells
-Thick peptidoglycan layer
-the pep layer is embedded with teichoic acids
What are three important characteristics of gram negative cells
-thinner layer of peptidoglycan
-gram negative cells have an outer membrane (which is why they stain pink instead of purple)
-the outer membrane contains LPS (the endotoxin)
what is the process called in which a vegetative cell transforms into an endospore
sporulation
what is a plasmid
DNA that is not part of the chromosomes in a prokaryotic cell that often carry advantageous genes like antibiotic resistance
where are prokaryotic ribosomes located within the cell
they are only found in the cytoplasm
what is the difference between fimbriae and pili
fimbriae are more numerous and shorter than pili
what is the purpose of fimbriae and pili
they make it easier for cells to attach to other cells and surfaces
what is the purpose of flagella
they help cells move in aqueous environments
what are the three components of a flagella
Basal body
Hook
Filament
what way do flagella spin to move the cell in a specific direction
if the flagella rotate counter clockwise the cell will move in a specific direction
what happens if flagella spin in a clockwise direction
the cell will just tumble in one spot
what is amensalism
when one participant is harmed and one participant is unaffected (think of a cow grazing on grass and is accidently stepping on insects cow is unaffected insects die)
what is commensalism
when one participant is benefited and the other is unaffected (think of a bird making a nest in a tree tee doesn’t care and bird is beniffited)
what is the definition of an infection
when a microorganism enters a host and begins to multiply
what is the definition of a disease
when a part of the host loses it’s normal function or structure
what are signs of a disease
objective and measurable qualities of a disease
what are symptoms of a disease
subjective conditions of a disease that a patient reports
What is the incubation period of a disease
the pathogen has entered the host and begins to multiply but no signs and symptoms are present yet
what is the prodromal stage of a disease
the pathogen has multiplied enough that the host begins to experience general signs and symptoms
What is the period of illness during a disease
specific signs and symptoms are present
What is the period of decline during a disease
the number of pathogen cells begin to decrease and the signs and symptoms decline
what is the convalescence period of disease
the host returns to normal function
what is pathogenicity
the ability of a pathogen to cause disease (it is either yes or no either it can cause disease or it can not)
what is virulence
a sliding scale of how bad the disease is if you were to contract it
what is vehicle transmission of a pathogen
when a common resource that many people access such as water or food is contaminated with a pathogen and then spreads
What is fomite transmission
when a single inanimate object is contaminated with a pathogen and only a small amount of people have access to that inanimate object
what is a passive carrier
contaminated with the pathogen and mechanically spread it but they are not actually infected
what is an active carrier
someone that is actively infected with a pathogen and spreads it (the may or may not have signs and symptoms)
are staphylococci gram positive or gram negative
they are gram positive Cocci
what is a virion
when a virus is outside a host cell and surrounded by a capsule which allows it to travel from one host to another
what shape is the top virus
icosahedral
what shape is the middle virus
Helical
what shape is the bottom virus
complex
can you have a virus with DNA and RNA
NO has to be one or the other
what structure surrounds the nucleic acid in a virus
the Capsid
what is capsid composed of
made of protein subunits called capsomeres
what is the difference between a naked virus and an enveloped virus
enveloped viruses are surrounded by a capsid and a lipid layer while naked viruses are only surrounded by capsid
what are viral spikes and what do they do
glycoprotein extensions on a virus that make it easier for a virus to enter a cell and also make it easier for a virus to detach from a cell during the release of new virions
what are the different stages of acellular host infection
Attachment
Penetration
uncoating
biosynthesis
maturation
release
what is the penetration phase of acellular host infection
when the viral genome is injected into the cell
what is the uncoating phase of acellular host infection
when the capsid is removed from the viral genome within the host cell
what is the maturation phase of acellular host infection
when new virions start to be manufactured within the host cell
what does it mean if virus RNA is positive sense
means that the RNA can be translated immediately by host cell ribosomes
What does it mean if virus RNA is negative sense
means it first has to be converted by RNA-dependant RNA polymerase before it can be translated by host ribosomes
what is different about a retrovirus and a normal virus
a normal virus turns RNA into proteins but a retrovirus turns RNA into DNA and then that new viral DNA is inserted into the host DNA
what does acid fast staining let you differentiate in bacterial cells
lets you differentiate between gram positive cells that have a waxy coating of mycolic acid and those that do not
What is a superinfection
a secondary infection that develops from a patient taking antibacterials that reduces the normal flora and allows another pathogen to replicate
what is descriptive epidemiology
describes the occurrence of disease within a population
What is analytical epidemiology
aims to gain knowledge on the quality and the amount of influence that different factors have on the occurrence of disease
what bacterial genus is commonly associated with opportunistic infections in immunocompromised patients in a health care setting
pseudomonas and staphylococcus
Where does replication of ssRNA viruses take place
Within the host cell cytoplasm
what is antigenic drift
minor shifts/changes in glycoproteins due to point mutations
what is antigenic shift
when major changes occur in virus glycoproteins due to genetic mixing with another virus
what does coagulase do
causes fibrin deposition which interferes with phagocytosis and increases pathogen’s ability to invade tissue
what would you see in a coagulase positive test
you would see clot formation because of the fibrin
what does obligate intracellular parasite mean
means that it needs a host in order to survive and reproduce
what is the lysogenic cycle
when the infection cycle leads to the integration of virus genome into the host genome
what is the lytic cycle
when the infection cycle leads to the death of the host cell
what is a prophage
when the virus genetic material is integrated into the host cell
what is a lysogen
what the cell is called when it is carrying the virus DNA
what are the two cycles that bacteriophages can have
lytic
lysogenic
what is tissue tropism
the ability of a pathogen to infect a specific type of tissue
what is different about the way a bacteriophage and an animal virus get their genome into a host cell
bacteriophages inject their DNA and animal viruses get in by endocytosis or membrane fusion
what is morbidity
how many people are in a state of illness
what is mortality
how many people have died in a population
what is the incidence of disease
the number of new cases over a specific time period
what is the prevalence of a disease
the number of individuals who have a disease at a particular point in time
what is a sporadic disease
one that occurs rarely and without geographic focus
what is an endemic disease
occurs at a constant low level within a population
what is an epidemic
local outbreak of a disease
what is a pandemic
a global outbreak of a disease
what does glycohydrolase do
degrades hyaluronic acid that cements cells together to promotes spread through tissue
how does nuclease help the spread of a pathogen
degrades DNA that usually traps bacteria so it promotes spread
what does proteases do
degrades collagen to promote spread of bacteria through tissue
is LPS a endo or exo toxin
it is an endotoxin
