Answer:
Bacteria are important because of their extreme flexibility and capacity for rapid growth and reproduction. <em>This statement is- TRUE</em>
Explanation:
Bacteria can grow best in their optimum environment. But they can survive in extreme conditions also.
Temperature- Optimum temperature for bacterial growth is 20- 45 degree Celsius. But Psychrophiles can survive on the lower temperature also . They can survive on refrigerator temperature lower than 4 degree Celsius.
Thermophiles even can grow on higher temperature up to 80 degree Celsius. Some hyperthermophiles has been discovered which can survive temperature ranging from 80-121 degree Celsius. Bacteria are discovered from hydrothermal vents where temperature is measured 340 degree Celsius. For bacteria obtained from hydrothermal vents optimal growth temperature is 100 degrees Celsius.
Like extreme temperature , bacteria can grow in extreme salt concentration are known as HALOPHILES.
Aerobic bacteria require oxygen to survive. But without oxygen also they can survive i,e. ANAEROBIC bacteria.
They can grow in highly acidic medium as well as highly alkaline medium.
They can survive in these extreme conditions , this flexibility and tolerance comes from their genes. Because of their very short duplication time /multiplication time they can achieve this tolerance. E. coli bacteria found in human intestine has very short doubling time of 20 minutes. They have ability to change /mutate their genes according to the survival condition. In genetic engineering also the advantage of using microbe with shorter duplication time is useful. Within few minutes one can get the result whether the desire gene is expressed or not.
