Any sort of nutrients-food particles, skin cells, blood, mucus-helps microbes thrive, which is why your kitchen sponge is a breeding ground. One popular method of killing bacteria using moist heat is boiling. Many of us boil water for minutes before drinking. We must remember that boiling can kill the bacteria but cannot kill all types of bacterial spores. Energy transmitted through space in a variety of forms is generally called radiation.
Bacteria are like all living organisms, they need to eat for energy and growth. But what do bacteria eat? Well, many bacteria eat starches and sugars which can be found on more or less all organic matter.
Most bacteria reproduce through binary fission, where a cell splits in two and creates an exact copy of itself. Other ways bacteria reproduce is through baeocytes which are very small cells and through budding when a daughter cells grow on the outside of a mother bacteria.
This is why acidic foods like lemon juice and vinegar do not support the growth of bacteria and can be used as preservatives. This is referred to as the danger zone see the section below for more information on the danger zone. Under optimum conditions, bacteria are capable of multiplying indefinitely at a very rapid rate, so that their numbers may double every 20 min or so. How quickly bacteria can multiply?
Category: medical health infectious diseases. Each type of bacteria has its own preferred conditions for growth. Under ideal conditions, many types of bacteria can double every 20 minutes. Potentially, one bacteria can multiply to more than 30, in five hours and to more than 16 million in eight hours. To calculate the number of bacteria at the end of the growth period, you can use this equation.
For a higher mark, you could express answers in standard form. For example, the above answer of , bacteria can also be written as 2. The mean division time for a bacterial population is 30 minutes. Calculate how many bacteria will be present after eight hours, when starting with one bacterium.
If after every 30 minutes there is one division, then after 60 minutes one hour there are two divisions. The mean division time for a bacterial population is 20 minutes.
Calculate how many bacteria will be present after two hours, when starting with 10 bacteria. As shown above, the exponential growth of bacteria can give very large numbers of bacterial cells in short periods of time.
Each type of bacteria grows best in a certain temperature range. Answer: 2, bacterias, because after 3 hours theyre bacteria so after 6 hours there will be bacterias so if its 9 hours you will have 2,00 bacterias.
The number of bacteria in a culture is increasing according to the law of exponential growth. After 3 hours, there are bacteria, and after 6 hours, there are bacteria.
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