Viruses_Lesson 13.2 Flashcards
(30 cards)
influenza is commonly known as the…
flu
what do the diseases chicken pox, mumps, measles, and polio have in common?
the are caused by different viruses
define “virus”
a nonliving strand of DNA or RNA surrounded by a layer of protein that can infect and replicate in a host cell
if you have had a cold, you have been infected by a…
virus
is a cell wall, a nucleus, or any other organelles present inside a virus?
no
the smallest viruses are between 20 and 100 times ______ than most bacteria
smaller
viruses have a _____ of shapes
variety
a cylinder, crystal, sphere, and bacteriophage are four common shapes of a…
virus
what are four common shapes of a virus?
cylinder, crystal, sphere, and bacteriophage
why do scientists NOT consider viruses living things?
they do not have all the characteristics of living things
what are the characteristics of all living things?
organization, response to stimuli, use of energy, growth, and reproduction
what characteristics of living things do viruses LACK
organization, response to stimuli, use of energy, growth, and reproduction
viruses, such as the Ebola virus, are considered to be…
nonliving
viruses must use organisms to…
carry on the processes associated with a living cell
because viruses have no organelles they are not able to…
take in nutrients, use energy, or replicate without using the cellular parts of an organism
how do viruses take in nutrients, use energy, or replicate without organelles
by using the cellular parts of a living organism
in order to replicate, viruses must…
be inside a cell
define “host cell”
the living cell that a virus infects
when a virus enters a cell, it can either be ______ or _____
active or latent
all latent viruses go through an _____ stage
inactive stage
what happens when a virus become latent?
it’s genetic material becomes part of the host cell’s genetic material
for a period of time known as the inactive stage, the virus does not…
take over the cell to produce more viruses
in some cases, viruses have known to be inactive for….
many years
once a virus becomes active…
it takes control of the host cell and replicates
