How does different temperatures produce different microbial growth rates?

Answer 1

Microbes grow in warm temperatures. But there is a limit, they need an optimum temperature to grow best.

Bacteria have an optimal temperature for growth, yes, but the temperature varies with the microbe.

Bacteria are split into classes based on where the optimal growth temp. falls. The edges of the groupings are fuzzy, but the approx. ranges are:

1. Extreme psychophiles (or psychotrophs) -- below -5oC

2. Psychophiles (or psychotrophs) -- -5oC to 25oC

3. Mesophiles-- 25oC to 45oC

4. Thermophiles-- 45oC to 70oC

5. Extreme thermophiles-- above 70oC

There is overlap and different sources will have different ranges, but these categories define bacterial habitat from Arctic ice to inside hydrothermal vents of sea floor volcanos. Food spoiles in the refrigerator because there are bacteria that grow at those tempreatures.

Answer 2

Different types of microbes thrive in different types of temperatures. Bacteria, for example, fall into two categories: psychrophiles can grow at temperatures around 20°C some below while thermophiles tend to grow at temperatures 45°C and above. Pathogens, on the other hand, generally thrive in the range of 5°C and 63°C.

Answer 3

Different temperatures affect microbial growth rates because each microorganism has an optimal temperature at which it thrives. Higher temperatures can denature proteins and disrupt cell membranes, slowing down or inhibiting growth. On the other hand, lower temperatures can reduce enzymatic activity and metabolic processes, also affecting growth rates.