Flu (influenza) viruses are divided into four broad categories: influenza A, B, C or D. Influenza A is the most common type. H1N1 flu is a subtype of influenza A.
Subtypes of influenza A are categorized based on two proteins on the surface of the virus, hemagglutinin (H) and neuraminidase (N). There are many H and N subtypes, and each one is numbered. All H and N flu subtypes are influenza A viruses.
Each influenza subtype has many different strains of influenza virus. Not all strains infect people. Subtypes of influenza A viruses currently found in people are strains of H1N1 and H3N2. Each year's flu vaccine includes varieties of both of these strains and influenza B.
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Water, sunlight, and carbon dioxide
A benefit of America having climate change is that we use lots of Factories and travel
Mutation rate of Gram negative bacteria is much greater than that of Gram positive bacteria.
Explanation:
The gram positive types of bacteria responsible for causing diseases in humans. It is called as Gram positive bacteria. Both the bacteria are different in structural and physical properties. It is defined as the group of bacteria’s which positive result in gram stain test.
Gram negative bacteria are the group of bacteria’s which gives negative result to the gram stain test. This classification is done according to the cell wall. The cause of common disease by Gram positive bacteria is our anthrax, diphtheria, etc.