What are Viruses ? | Types, Definition, Structure, Function & Facts

What are Viruses?

Viruses are very small particles that can infect animals and plants and make them sick. Viruses are made up of genetic material such as DNA and protected by a layer of protein.

Viruses attack cells from living organisms. They inject their genetic material directly into the cell and take over. They then use the cell to make more viruses and take over more cells.

Are Viruses Alive?

Scientists differ on whether the virus is actually alive or not. Many say they are not alive because they cannot reproduce without the help of a host. Viruses also do not convert food, into energy or have the cellular organization that is common to living organisms. Features of viruses

Characteristics of Viruses

They do not have an organized cellular structure.

They do not have a cell nucleus.

They usually have one or two strands of DNA or RNA.

They are coated with a protective protein called CAPSID.

They are inactive when not inside a living cell, but active when inside another living cell.

Why are Viruses bad?

When viruses enter the body’s cells and begin to multiply, they make the host sick. Viruses can cause all sorts of diseases.

How do Viruses spread?

Viruses are very small and mild. They can be suspended in the air, exist in water or even on the surface of your skin. The virus can be passed from person to person by shaking hands, touching food, through water, or through the air when someone coughs or sneezes.

The virus can also be transmitted through the bite of an insect, animal, or unhealthy food.

Examples of Viruses

Many viruses can infect people and make them sick. One of the most common illnesses is the flu, which causes the flu. Other illnesses caused by viruses include the common cold, measles, mumps, yellow fever, and hepatitis.

How to Avoid Getting Infected

There are things you can do to help reduce your chances of getting the virus. Here are some examples:

Wash your hands (probably one of the most important).

Do not put your hands or fingers in your mouth, nose or eyes.

By rubbing your nose or eyes, the virus on your hands can infect your body.

Make sure your food is thoroughly cooked, especially meat.

Take vitamins every day.

Get plenty of sleep and exercise. This helps boost your immune system to fight the virus.

How are Viruses treated?

Doctors can’t do much to treat the virus. In most cases, our body’s immune system fights off the virus. Scientists have developed vaccines that help our bodies build immunity against a specific virus. An example of a vaccine is the flu vaccine. The flu vaccine helps the body develop its own defenses against the flu called antibodies.

Interesting Facts about Viruses

Viruses are not classified in any of the five kingdoms of living things. This means they are not bacteria, fungi, protozoa, plants or animals.

Most viruses are so small that they cannot be seen under a light microscope.

The word “virus” comes from the Latin word “virulentus” which means “malicious”.

Viruses can sometimes attack and kill bacteria.

The first human virus to be discovered was the yellow fever virus in 1901 by Walter Reed.

Viruses that contain RNA instead of DNA are sometimes called retroviruses.

There are two main types of viral reproductive cycles: the lytic cycle and the physiological cycle.

Diseases caused by lytic viruses show symptoms much more rapidly than those caused by lytic viruses.