|Can we describe viruses as being parasitic?|
|Question Date: 2017-01-14|
A parasite is something that harms an
individual of one species (host) and helps an
individual of another species (parasite). It’s
different from predation because in
predation, the victim has to die for the predator
to get the benefit. A host sometimes dies from
having too many parasites, but if that’s just a
side effect, it still isn’t predation. Sometimes a
parasite does better the longer its host lives.
For example, if a tapeworm is living in someone’s
gut, the worst thing that can happen for the
tapeworm is for its host to die. With a parasite
like a tick, it doesn’t really matter to the tick
whether you live or die after it takes your blood.
Parasites and hosts don’t have to be
animals. For example, vines might grow on top
of other plants, using the big plant’s height and
taking sunlight away from the host plant’s leaves.
An insect might burrow into a tree and take its
Viruses move into cells and turn them into
virus factories. The cell usually bursts when
it fills with viruses. The cell that they take
over could be one in the lining of your nose or
the leaf cell of a tree.
Viruses are not technically alive, but they’re
close. The nose or leaf cells are alive.
So what do you think? If you are not 100%
sure, keep in mind that we humans like to make
neat and tidy categories, but the natural world
doesn’t always fit in neatly.
Thanks for asking,
Great question! We cannot describe viruses as
being truly parasitic for a few reasons .
First, parasites are living organisms that live in
or on another organism (the host) and take away
nutrients from the host for the parasites own
growth. Although there has been a lot of debate
about whether viruses are living organisms,
most virologists (scientists who study viruses)
agree that they are non-living because they do
not meet all of the criteria for life. Second,
viruses are able to live outside of a host
body while parasites are dependent on a
living host to survive. However, parasites and
viruses are similar in that they can both cause
damage to other living organisms that live inside.
Although they have some similarities, we are not
able to call viruses parasitic.
Yes, in terms of how they interact with (other)
living things, viruses are usually parasites
(although not always).
Viruses are generally considered to be
parasitic since their survival always steals away
resources from their host. Often viruses will
deliberately harm the host and sabotage its
ability to fight back. Though generally when
people use the term “parasite”, they are
specifically referring to parasitic organisms that
aren’t bacteria or viruses such as worms or
the organism that causes malaria. So generally
viruses are problematic for the host organism
which makes them parasites. Interestingly enough,
this isn’t always clearly the case. Nature is
complicated so sometimes what seems like a
negative for the host can actually be a positive.
For instance, certain viruses prime the body to
attack against bacteria so can be helpful. Also,
bacteriophages which are viruses that
infect bacteria can help protect a human from
bacteria. There are even viruses that can make a
plant drought tolerant! In these cases,whether
a virus is parasitic or mutualistic
(benefiting both organisms) is more complicated.
The virus may still cause some harm, but also has
a role in benefiting the host.
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