[Solved] Consider the following: Some microorganisms can grow in environments with temperature above the boiling point of water. Some microorganisms can grow in environments with temperature below the freezing point of water. Some microorganisms can grow in highly acidic environment with a pH below 3. How many of the above statements are correct?

Q88. Consider the following:

1. Some microorganisms can grow in environments with temperature above the boiling point of water.
2. Some microorganisms can grow in environments with temperature below the freezing point of water.
3. Some microorganisms can grow in highly acidic environment with a pH below 3.

How many of the above statements are correct?

1. Only one
2. Only two
3. All three
4. None

Answer: 3

Statement 1 is correct: A thermophile is an organism, a type of extremophile, that thrives at relatively high temperatures, between 41 and 122 °C. Most thermophiles live at temperatures between 60 and 80 ° C. Thermophiles are capable of growing, carrying out metabolic processes, and reproducing at these extreme temperatures. One thermophile, Pyrolobus fumarii, has been found at temperatures of 113° C /235° F, which is hotter than the boiling point of water.

Statement 2 is correct: Psychrophiles are organisms capable of growth and reproduction in cold temperatures and are often xerophilic and halophilic as well. Some microbes will cease growing at zero degree Celsius or even higher while others continue to grow below the freezing point of food. Growth rate below 0C is very slow. The reported minimum growth of microorganisms varies from 100C to – 100C. But for practical cases, the lower limit of growth for bacteria, yeast or moulds can take as -70C.

Statement 3 is correct: Acidophiles are microorganisms that show optimal growth in highly acidic environments. These are of two types. The extreme acidophiles dwell in environments with a pH value <3, and moderate acidophiles grow optimally in conditions having pH values ranging between 3 and 5.