മൗവ്വഞ്ചേരി യു പി സ്കൂൾ/അക്ഷരവൃക്ഷം/Coronaviruses

Coronaviruses Coronaviruses are a group of related viruses that cause diseases in mammals and bird. In humans, coronaviruses cause respiratory tract Infections that can range from mild to lethal. Mild illnesses include some cases of the common cold , while more lethal varieties can cause ,SARS, MERS, and COVID19. Symptoms in other species vary: in chickens, they cause an upper respiratory tract disease, while in cows and pigs they cause diarrhea. There are yet to be vaccines or antivirul drugs to prevent or treat human coronavirus infections. Coronaviruses constitute the subfamily Orthocoronavirinae, in the family Coronaviridae, order Nidovirales, and realm Riboviria.They are enveloped viruses with a positive – sence single standerd RNA genom and a nuecliocapsid of helical symmetry. The genome sizeof coronaviruses ranges from approximately 26 to 32 kilobases, one of the largest among RNA viruses.They have characteristic club-shaped spikes that project from their surface, which in electron micrographs create an image reminiscent of the solar corona from which their name derives. 💐💐💐💐💐💐💐💐💐💐💐💐💐💐 🍁 Drishya Sunil Kumar 🍁 6 A മൗവ്വഞ്ചേരി യു പി സ്കൂൾ കണ്ണൂർ നോർത്ത് ഉപജില്ല കണ്ണൂർ അക്ഷരവൃക്ഷം പദ്ധതി, 2020 ലേഖനം