Question

Barophilic prokaryotes
A. Grows slowly in highly alkaline frozen lakes at high altitudes.
B. Occurs in water containing a high concentration of barium hydroxide
C. Grows and multiply in very deep marine sediments
D. Readily grows and divide in seawater enriched in any soluble salt of barium

Answer 1

Hint: Baro is a term that is used concerning pressure. The barometer, for example, is used in measuring the atmospheric pressure.

Complete answer:
Barophilic prokaryotes are organisms that thrive under very high-pressure conditions. Barophile means pressure loving. These prokaryotes prefer to grow in regions of high hydrostatic pressure. They are found under the sea at great depth where hydrostatic pressure is extremely high.

Additional Information:
- The barophilic bacteria are of three types, barotolerant which grow at pressures ranging from 100-500 atm, barophilic which grow at pressures ranging from 400-500 atm and extreme barophilic which grow at pressures higher than 500 atm.
- Examples of some barophilic bacterias are Colwellia, Shewanella, Moritella, etc.
- These prokaryotes show certain adaptations that help them survive under high pressure like the increased binding ability to enzymes, more number of PUFA(polyunsaturated fatty acids) in the cell membrane, etc.
- These barophilic bacterias are found in the Mediterranean Basin and the Mariana Trench (Extremely Barophilic prokaryotes)
- With the increase in atmospheric pressure, the growth and reproduction rate of these prokaryotes increases enormously.
- Other categories of prokaryotes also exist which thrive under extreme conditions and are known as extremophiles. Acidophiles live under highly acidic conditions, alkaliphiles live in alkaline regions, thermophiles are found in deep-sea vents and survive in extreme temperatures and psychrophiles survive in extremely cold conditions like the arctic and alpine lakes.

So, the correct answer is ‘Barophilic prokaryotes grow and multiply in very deep marine sediments’.

Note: The term piezophile is also used for describing barophilic prokaryotes and both of them have the same meaning.