Category: 

What are Some Properties of Viruses?

Article Details
  • Written By: Michael Anissimov
  • Edited By: Bronwyn Harris
  • Last Modified Date: 11 November 2016
  • Copyright Protected:
    2003-2016
    Conjecture Corporation
  • Print this Article
Free Widgets for your Site/Blog
The Argentinian resort town of Epecuén was submerged by flooding for years; it is now populated by one elderly man.  more...

December 5 ,  1933 :  Prohibition ended in the US.  more...

There are a number of different properties that distinguish viruses from other organisms. They are extremely small, with a size range between 10 and 300 nanometers. This is about ten times smaller than bacteria. Viruses cannot survive on their own, and depend on hijacking the protein synthesis machinery of living cells to reproduce. Because of this, they are sometimes not considered true living things, but are instead called "organisms at the edge of life." The domain name "Acytota" (meaning "without cells") has been attributed to these organisms, but it does not receive wide use. Most scientists do not consider them to be alive.

Viruses are bits of genetic material, like a length of instruction tape, covered in a small protein shell called a capsid. Sometimes, they have very basic "appendages," such as filaments or tail fibers, such as in bacteriophages (bacteria-killing viruses), but often, they are just a small package. Their shape may be helical, like a screw; icosahedral, like a geodesic dome; pleomorphic, like a little sponge; or resemble a bizarre spider robot out of science fiction, as in bacteriophages.

Ad

Instead of typical organisms, which reproduce via cell division, viruses reproduce at a hyper-exponential rate by infiltrating cells and using their protein synthesis machinery to pump out copies of the virus. In just ten minutes, a virus may take over a cell, copy itself hundreds of times, and kill the cell. Some viruses have a calculated replication time of about 70 seconds. By comparison, the fastest bacterial replicators only double their biomass every 20 minutes or so.

Viruses do not evolve or develop in ways similar to conventional living things. They do mutate and evolve, but some may originate as rogue mobile genetic elements (transposons) from the genomes of bacteria, plants, or animals. This means that they may lack a conventional "family tree" that other organisms possess. Because these organisms do not fossilize well, studying their past can be very difficult. Examining them directly requires an expensive electron microscope.

Ad

You might also Like

Recommended

Discuss this Article

Kristee
Post 4

@Perdido – There are types of virus protection for both the human body and for computers. I am so scared of viruses that I have both.

I get a flu vaccine every year, and it seems to keep me from getting so much as a cold. I know it isn't designed to protect against anything but the flu, but I just don't get sick during winters when I have gotten the vaccine.

Also, I have some virus protection software installed on my computer. I keep it updated so that I am always protected. I did have a computer virus once before I got the software, and it wiped out everything I had.

Oceana
Post 3

The worst of the human viruses that I have ever had has got to be rotavirus. I caught this when I was only nine, and I had to be hospitalized for a week.

I wasn't allowed to have visitors, other than my parents, because it was so highly contagious. I had severe diarrhea, vomiting every few minutes, and a fever. I would have quickly dehydrated if I hadn't gotten help.

I have never been that sick since, not even when I caught the flu. Thankfully, there is now a rotavirus vaccine for kids.

Perdido
Post 2

@seag47 – What scares me is that they kill the host cell after it has basically been turned into their very own copy machine. Once the cell dies, it releases the copies of the virus.

I've had everything from the flu virus to a computer virus, and all of them spread rapidly. I caught the flu at school, and so many students wound up with it that they had to shut down school for a week. I caught the computer virus from a forwarded email, and it had already affected many people.

seag47
Post 1

It's scary that viruses can replicate so rapidly! I knew that they were capable of copying themselves, but I had no idea they could do this in as little as 70 seconds.

Post your comments

Post Anonymously

Login

username
password
forgot password?

Register

username
password
confirm
email