BIO-Classification of systems, page no 21
Viruses are microscopic organisms that can infect hosts, like humans, plants or animals. They're a small piece of genetic information (DNA or RNA) inside of a protective shell (capsid). Some viruses also have an envelope. Viruses can't reproduce without a host.
Some examples of viruses:
Covid-19: COVID-19 is caused by a type of coronavirus called SARS-CoV-2. The virus spreads: Mostly through the air, in droplets that an infected person spreads through a cough, sneeze, singing, or talking.
Bubonic plague: Bubonic plague is an infection spread mostly to humans by infected fleas that travel on rodents. Called the Black Death, it killed millions of Europeans during the Middle Ages. Prevention doesn't include a vaccine, but does involve reducing your exposure to mice, rats, squirrels and other animals that may be infected.
Chicken pox: Chickenpox is caused by the varicella-zoster virus. Chickenpox is very contagious. Symptoms include an itchy, blister-like rash in addition to other symptoms. Chickenpox illness usually lasts about 4 to 7 days.
Dengue: Dengue (break-bone fever) is a viral infection that spreads from mosquitoes to people. It is more common in tropical and subtropical climates. Most people who get dengue will not have symptoms. But for those who do, the most common symptoms are high fever, headache, body aches, nausea, and rash.
Questions for Everybody{ Not really compulsory}:
Are viruses living or non-living?
How does covid-19 spread?
What can cause the Bubonic plague?
What are symptoms of Dengue?
How to viruses reproduce?
THE END
Now everybody stop asking questions.
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