Question

11) Describe the quantitative measurements of Bacterial growth?
Deline viruses. What are the properties of viruses. Describe two methoots for
isolation g viruses.​

Answer 1

Answer:

A virus is a small infectious agent that replicates only inside the living cells of an organism. Viruses can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea.[1]

Virus

"Rotavirus"

Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants, and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898,[2] about 5,000 virus species have been described in detail,[3] of the millions of types of viruses in the environment.[4] Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity.[5][6] The study of viruses is known as virology, a sub-speciality of microbiology.

Answer 2

Answer:

Quantitative measurements of Bacterial growth

As bacteria are unicellular and divide asexually the growth of the population can be followed either by the changes in number of cells or weight of cell mass. Examples of methods are turbidimetric measurements, direct microscopic count or viable count.

Viruses

A virus is a small infectious agent that replicates only inside the living cells of an organism.

The properties of viruses

Viruses are the smallest infectious agents and contain only one kind of nucleic acid (RNA or DNA) as their genome. The nucleic acid is encased in a protein shell, which may be surrounded by a lipid-containing membrane. The entire infectious unit is termed a virion.

Isolation of Viruses

Virions in the liquid medium can be separated from the host cells by either centrifugation or filtration. Filters can physically remove anything present in the solution that is larger than the virions; the viruses can then be collected in the filtrate.