NEET BIOLOGY

Detailed explanation-1: -The result of the calculation is that the best estimate of the number of bacteria and archaea on Earth is about 3 × 1031, and the best estimate of the virus number is barely more than 1031.

Detailed explanation-2: -There could be over 320, 000 different viruses that infect mammals out there, many of which are harmless, whilst some might actually provide benefits to us. For example, some viruses called bacteriophages attack bacteria in our bodies and so have a crucial role in regulating our microbiome.

Detailed explanation-3: -A key step in the virus evolutionary journey seems to have come about around 1.5 billion years ago – that’s the age at which the team estimated the 66 virus-specific protein folds came on the scene. These changes are to proteins in the virus’ outer coat – the machinery viruses use to break into host cells.

Detailed explanation-4: -Viruses are 100 times smaller than bacteria and can only be seen through the highest form of microscopy. They become easily airborn and this is why viruses often enter the human body through our respiratory systems.