7. What are viruses and what is COVID-19?


Viruses are the smallest micro-organisms and they are all pathogens, meaning that they all cause disease. Viruses do not carry out MRS C GREN, the only life process they do is reproduction and even then they can’t do that by themselves they need another living cell to be a host. This makes viruses non-living. Viruses affect all living things, bacteria, fungi and animals by hijacking their cells and using them as virus making factories.

Viruses have some genetic material that are the instructions for how the virus works, surrounded by a capsid which is layer that protects the genetic material. Some viruses have an outer layer made of lipids (another name for fats) that have spikes stuck through them. The virus uses these spikes to attach to a cell they are trying to infect. The spikes are also how our body recognises different viruses.

In early 2020 the virus responsible for the illnesses and deaths was identified as a coronavirus and it was given the name severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The illness the virus caused was called COVID-19 (CO = corona, VI = virus, D = disease and 19 = the year it was first seen = 2019). When viewed under a powerful microscope coronaviruses look a little bit like crowns (corona in Latin means crown).

This virus causes a cough, fever and shortness of breath. The cough is because the virus causes inflammation and fluid build-up in the lungs meaning the lungs are irritated and trying to get rid of the fluid. The fever is due to the body trying to stop some of the virus parts from working by exposing them to high heat. The shortness of breath is because the lungs are not able to fully inflate and get oxygen into the blood.

We now know that the virus is transmitted is small droplets of liquid that come out of your mouth and nose when you talk, sing, cough or sneeze. The droplets can also get onto you hands and anything you touch. Transmitted means the virus moves from an infected person to a non-infected person.


Corona: Means 'crown' in Latin.

Reproduce: Being able to make copies of themselves

Capsid: The layer in a virus that protects the genetic material.

Non-living: Do not carry out the life processes of MRS C GREN.

COVID-19: The illness caused by SARS-CoV-2.

SARS-CoV-2: Severe acute respiratory syndrome coronavirus 2

Virus: Millions of bacteria in one spot on an agar plate.

Spikes: Structures that stick out from the surface of a virus. They are used to stick to host cells when viruses is using them to reproduce. The bodies immune system can recognise these spikes and make antibodies that make the spikes unable to stick to host cells.