The origin and essence of viruses
What is a virus?
In these times of pandemic, we hear a lot about “viruses,” but what exactly is a virus and why does it affect us? According to biology, a virus is a microscopic agent that can only multiply (replicate) inside the cells of an organism using its own genetic material and taking advantage of the cell's replication mechanisms. In other words, viruses need to infect a living cell to control it, causing the cell to reproduce a large number of viruses using its own biological material and machinery.
Viruses are much smaller than cells and bacteria, and therefore can only be seen with an electron microscope. Comparatively, a eukaryotic cell can measure between 10 and 100 µm , bacteria measure between 0.5 and 5 µm, while viruses measure between 10 and 100 nanometers.
Viruses are actually genetic material (fragments of DNA or RNA ) protected by a shell called a capsid , which is composed of lipids (fats) and proteins to keep the virus intact until it finds a host cell to infect. Viruses can infect all kinds of organisms, including animals, plants, fungi, and bacteria. The virus's main vulnerability is its capsid. Due to the capsid's lipid nature, soap can break it down, deactivating the virus. That's why the first line of defense against viruses is washing with plenty of soap and water.
What is the nature of viruses?
Viruses are fragments of DNA or RNA protected by a capsid. When they infect a cell, viruses force the cell to produce identical viruses. Viruses can infect all types of organisms, including animals, plants, fungi, and bacteria. Viruses can be classified into three main groups: viruses with DNA as their genetic material, viruses with an RNA genome, and viruses that use both RNA and DNA as genetic material.