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Explain how bacteria possess an ‘optimum temperature’ for growth - helpp pleasee

I honestly dont know what to write for this question: explain how bacteria possess an ‘optimum temperature’ for growth

Maybe this?? Bacteria with higher optimal growth temperatures will grow faster than those species with lower optimal growth temperatures.
use the wording of the question as a guide
Reply 2
It just comes up with this: Bacteria that grow at temperatures in the range of -5oC to 30oC, with optimum temperatures between 10oC and 20oC, are called psychrophiles. These microbes have enzymes that catalyze best when the conditions are cold, and have cell membranes that remain fluid at these lower temperatures.

What exactly is the question asking
Reply 3
Original post by tinygirl96
use the wording of the question as a guide

It just comes up with this: Bacteria that grow at temperatures in the range of -5oC to 30oC, with optimum temperatures between 10oC and 20oC, are called psychrophiles. These microbes have enzymes that catalyze best when the conditions are cold, and have cell membranes that remain fluid at these lower temperatures.

What exactly is the question asking
the question is evaluating your scientific knowledge
It says "explain" so I think you need to give examples and explain why bacteria grows faster at a certain temperature and the trends in the growth of bacteria relating to the temperature. Check the internet, because we partly covered this topic, but I'm only in Year 9.
(edited 2 years ago)
Reply 6
Original post by zarahh09
I honestly dont know what to write for this question: explain how bacteria possess an ‘optimum temperature’ for growth

Maybe this?? Bacteria with higher optimal growth temperatures will grow faster than those species with lower optimal growth temperatures.

Hello!

This question is specifically testing your knowledge of how temperature affects growth; it needs you to explain (so describe factors that influence and WHY they influence the relationship) what happens between a certain temperature range (lets say 20-30 degrees centigrade for common bacteria) that causes them to grow FASTER/SLOWER than at an alternate temperature range (-5 to 0 degrees for example).

Involved in bacterial growth at a macro level is cell division. The implication being there are processes within the cell occuring - DNA replication for example. This uses enzymes and chemical reactions to occur. Have you been taught the effect of temperature on these? (Hint: they have an optimal temperature for rapid reactions).

Let me know if you need any more clues :smile:
Reply 7
Original post by siarc
Hello!

This question is specifically testing your knowledge of how temperature affects growth; it needs you to explain (so describe factors that influence and WHY they influence the relationship) what happens between a certain temperature range (lets say 20-30 degrees centigrade for common bacteria) that causes them to grow FASTER/SLOWER than at an alternate temperature range (-5 to 0 degrees for example).

Involved in bacterial growth at a macro level is cell division. The implication being there are processes within the cell occuring - DNA replication for example. This uses enzymes and chemical reactions to occur. Have you been taught the effect of temperature on these? (Hint: they have an optimal temperature for rapid reactions).

Let me know if you need any more clues :smile:

I understand it now thankyouu :smile:
They are testing your knowledge so you need to explain the factors that influence, what happens and what we mean by Fast and Slow rate. How the reactions are affected? The DNA etc...
Good luck
Original post by zarahh09
I honestly dont know what to write for this question: explain how bacteria possess an ‘optimum temperature’ for growth

Maybe this?? Bacteria with higher optimal growth temperatures will grow faster than those species with lower optimal growth temperatures.


Bacteria that grow at temperatures in the range of -5oC to 30oC, with optimum temperatures between 10oC and 20oC, are called psychrophiles. These microbes have enzymes that catalyze best when the conditions are cold, and have cell membranes that remain fluid at these lower temperatures.
Optimum Values: Somewhere between its characteristic upper and lower temperature ...
Background: Microbes, even if they are supplied with all the necessary nutritional re...
Conditions: Each investigation is carried out under a specific set of growth conditions. ...
Tools of the Trade: In these investigations, a tiny group of each microbe species are ...
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Bacteria, single celled eukaryotes and other microbes, can only live and reproduce within a certain range of environmental conditions. Factors that can influence if or how microbes can grow are temperature, pH, dissolved gases, osmotic pressure and water availability.

Microbes, such as bacteria are more tolerant of environmental conditions than other organisms. However, each species has its own characteristic and particular range of values in which it grows and reproduces best.

Upper and Lower Values, and Temperature Range Some species of microorganism can grow at temperatures as low as -10o C, and others at temperatures as high as 100o C - or higher. These upper and lower values are a function of cell metabolism. At lower temperatures molecules move slower, enzymes cannot mediate in chemical reactions, and eventually the viscosity of the cell interior brings all activity to a halt.

As the temperature increases, molecules move faster, enzymes speed up metabolism and cells rapidly increase in size. But, above a certain value all of these activities are proceeding at such high rates, enzymes start to denature, and the total effect is detrimental. Cellular growth ceases.

These boundary values define the maximum and minimum temperature at which life can exist (and grow). Each species of microbe has its own, unique upper and lower limit, which is a defining characteristic for that species.

Optimum Values
Somewhere between its characteristic upper and lower temperature limits, each species of microbe has a particular temperature at which it grows best. At this temperature all aspects of the cell metabolism function at their optimum values, the cell is able to rapidly increase in size and divide. When members of a species find themselves living at their optimum temperature, their growth rate is at its maximum value.

Psychrophiles

Bacteria that grow at temperatures in the range of -5oC to 30oC, with optimum temperatures between 10oC and 20oC, are called psychrophiles. These microbes have enzymes that catalyze best when the conditions are cold, and have cell membranes that remain fluid at these lower temperatures.

Sea water near the poles of the earth are rich in algae that can live below 0oC, and the psychrophilic bacteria that spoil milk, meat, vegetables and fruit are perfectly happy growing in a refrigerator. Although refrigeration is a good way of slowing down food spoilage, it cannot stop the growth of these bacteria.

Mesophiles

Microbes that grow at optimal temperatures in the range 20oC to 40oC, are called mesophilic. Important members of this group are those that live in and on warm blooded creatures, such as humans. Pathogenic bacteria and included here, as are symbiotic bacteria that live in the human body without harming it.

Thermophiles

Certain bacteria can live and grow at temperatures that exceed 50oC. These are thermophilic microbes that can tolerate the very harsh conditions decomposing organic material.

Tools of the Trade
In these investigations, a tiny group of each microbe species are placed into a liquid, nutrient filled broth that has been sterilized (so no other bacteria will compete!). Usually this is in a special flask (called an "Erlenmeyer flask"), which is slowly shaken (to keep the microbes and nutrient at uniform distributions).
Each growing culture is carefully kept at the appropriate, and constant, temperature for the length of the experiment.

At regular intervals of time, small samples of the growing culture are taken from the flask and all reproduction of the microbes stopped by some poison or inhibitor (they can also be chilled or frozen). The size of the population at each time point is then determined.

The results of each of your investigations should be recorded as a table (a Table of Results). In these tables you should indicate the name of the microbe being studied, the temperature growth, and make an accurate record of either the growth data (growth curve), or the value of the generation time (generations per minute), as required.

The shape of these graphs or plots is characteristic for each species of microbe, but each organism will show an optimum temperature where growth proceeds most rapidly, and as the temperatures either exceed, or fall below that optimum, growth slows down. Above or below the maximum and minimum permissive temperatures, all growth stops.

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