Diseases of the 21st century Flashcards
otherwise known as causative agents; in the form of viruses, bacteria, fungi, and parasites
etiologic agents
they are emerging and re-emerging
virus
neither prokaryotic nor eukaryotic
virus
viruses are submicroscopic: they are view under _______ only
electron microscope
they are _____ intercellular parasite: viruses have the ability to use the machinery of the host cells to reproduce. they do not have their own cell organelles, hence they cannot reproduce or live separately)
obligate
Host TROPISM: infect host cell for HIV
CD4 cells (immune cell)
Host TROPISM: infect host cell for HBV
hepatocytes (liver)
smallest DNA virus
parvovirus
largest DNA virus
poxvirus
smallest RNA virus
picornavirus
largest RNA virus
paramyxovirus
the emerging virus are ____ virus
novel virus
emerging viruses are called these because it is the very first time that the scientists are able to discover or characterize the virus (how it affects exposed)
novel viruses
these viruses are discovered before and there was a time when this virus was eradicated but it came back sometime in the future
re-emerging viruses
they are unicellular organisms that lack membrane-bound structures or nucleus
prokaryotes
organisms whose cells have nucleus and other organelles enclosed by a plasma membrane
eukaryotes
(PAPAF)
examples of eukaryotes
plants, animals, fungi, algae, protozoans
if the virus is outsiDe the host is considered
dormant
if the virus is inside the host, it is
activated
DNA and RNA viruses are existing because of the presence of an ______________ core in a particular virus consisting of either DNA or RNA
inner nucleic acid core
the inner nucleic acid core is protected by a protein coat known as the
capsid
structure of a virus
it is naked or enveloped
in a virus =, what are structures present
- genome
- capsid
- nucleocapsid
- spikes
- tegument
- envelop
where the RNA or DNA
genome (nucleic acid core)
protein layers covering the genome
capsid
genome + capsid
nucleocapsid
glycoprotein responsible for attachment or adsorption of cell
spikes
matrix separating envelop from nucleocapsid
tegument
external glycoprotein/lipid covering the nucleocapsid taken from the host
envelop
the only structures present in the naked virus are the
genome, capsid, and nucleocapsid
naked viruses are more resistant to extreme pH, heat, dryness, and simple disinfectant. because of their ________, these are transmitted via the fecal-oral route.
stability
examples of naked viruses
norovirus, enterovirus, adenovirus, and rhinovirus are all
naked viruses are typically more ________ (harsh) than enveloped viruses.
virulent
why does the naked viruses are more virulent than enveloped viruses?
because they usually cause host cell lysis.
the most common exit mode from the host cell by the naked virus
cell lysis
the viruses violate the integrity of the ______________l causing cell death and significant tissue damage to the host organism.
cell membrane
these viruses are very susceptible to drying out and destruction or environmental changes .
enveloped viruses
these viruses are transmitted via direct contact through respiratory, sexual or parental contact.
enveloped viruses
in this way, it prevents the virus from being exposed to the environment and it would lead to a successful propagation of the viral agent to another susceptible host.
the transmission of the enveloped viruses
enveloped viruses are less virulent because they don’t always cause ____ during cell exit, although cell death often follows as a consequence of virus replication.
cell lysis
Since enveloped
viruses contain an extra ______ or an _______that surrounds the capsid, during virus
assembly and exit from host cells, these viruses
can use the host cell membrane itself to assemble
their membrane, known as an ________
bilipid layer or an outer
membrane; envelope
