-
virus is made up of?
genome and capsid
-
-
smaller protein units that make up the capsid
capsomers
-
nucleocapsid
the genome and the capsid
-
addition items of a virus.
envelope and spikes
-
envelope is
an enclosing structure similar to membrane that encloses a host cell
-
at which stage is the enveloped acquired?
the last stage of replication
-
spikes are?
projections from envelope to help make contact with the host's cell
-
virus is ...
a core of nucleic acid, have protein covering, some with envelope, no chemistry, takes up no nutrients, no waste, no metabolism, BUT replicates
-
what are some viral shapes?
- helical viruses
- -icosahedral viruses
- -complex viruses
-
helical viruses are...
- tightly wound coil
- ex. rabies virus, measles virus
-
icosahedron ...
- polyhedron with 20 triangular faces
- ex. herpes virus, parvovirus, poliovirus
-
complex virus ...
eg. influenza virus, smallpox, bacteriophage
-
components of a virus?
capsid, genome, capsomeres, envelopes spikes
-
stages of replication
- 1. attachment
- 2. penetration
- 3. uncoating
- 4. synthesis
- 5. assembly
- 6. release
-
What stage is there the virus anchors on to receptor sites on the host?
attachment stage
-
At this stage, the cell eventually break out
release stage
-
at this stage, the capsid is removed
uncoating stage
-
at this stage, the genome passes thru the host membrane
penetration stage
-
at this stage, the affected makes the virus
-
at this stage, everything's put together after the viral parts are complete
assembly stage
-
what is the virus doing to host?
- -inhibit host's DNA/RNA/protein synthesis
- -disrupt chromosomes
- -high concentration of viral proteins inside host, which makes it toxic
-
acute infections (viral infection)
come on quick but last for short duration
-
persistent infection (viral infection)
can last many years
-
chronic virus infection.
- virus is almost always detectable
- -shows clinical symptoms, but mild or absent for long periods
-
latent infections (viral infections)
virus stops reproducing and remains dormant for some time; during latent stage, symptoms, viruses, and antibodies are not detectable
-
When viruses don't replicate, it's called ...
lytic cycle, aka lysogenic cycle
-
defense against virus.
antibodies, drugs, vaccine (weakened virus so body can rid of it)
-
vaccines
- 1. inactivited: capsid's ok but no genome
- 2. intenuated: "live" virus that's working erally slowly, extremely slow replication
- 3. genetically engineered
-
viroids are.
simpler than virus, protein-like, and cause disease in plants
-
Eukaryotes..
- -contrast wit prokaryotes, have a membrane bound nucleus
- -mitochondria (site for respiration)
- -chloroplasts, in photrophic cells, larger than mitochondria
- -other internal structures
- -external structures: flagella, cilia
-
Protozoa.
unicellular, usually motile, lack cell wall, generally colorless, no chlorophyll, motility
-
active feeding form of protozoa
trophozoite
-
protective form or 'resting state' of protozoa
cyst
-
4 major groups of protozoa.
- 1. amoebas
- 2. flagellates
- 3. ciliates
- 4. sporozoa
-
amoebas.
- move by false feed "pseudopodia", heterotrophs (need organic carbon for growth); some have shell-like carings
- ex: forminifera: calcium carbonate, radiolaria: silicon dioxide
-
flagellate
some phototrophic, most fundamental protists
-
Ciliates
diverse group of heterotrophic; move using hair-like cilia and some motile
-
sporozoa.
all obligated parasites
|
|
