Which of the following is a pathogen that could not be identified by the original koch’s postulates?
staphylococcus aureus
pseudomonas aeruginosa
human immunodeficiency virus
salmonella enterica serovar typhimurium

Human immunodeficiency Virus.

Explanation:

According to Koch postulates the The microorganisms can be grown on pure culture( postulate 2).

But the human immunodeficiency virus cannot be grown on pure culture. Without a suitable not human host a researcher cannot evaluate postulate 2.

Human immunodeficiency virus needs host cell to grow it does not use any other animal as a host cell so this virus does not follows Koch postulates.

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.

the sun's light combined with the visible wavelenghts form what is called ultraviolet radiation, which are the long waves at the end of a visible light sprectrum.

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