Bacteria are the smallest living things..........bacteria from growing and multiplying as there is insufficientmoisture.

Bacteria are the smallest living things with a cellular structure; each individual bacterium consisting of one single colorless cell, which is usually either spherical or rod-shaped. Individual bacteria measure from 0.0001 inches to 0.00001 inches in length, so they can be seen only with the help of a high-power microscope. They are so small that they can float in the atmosphere, usually as 'passengers' on dust particles, up to a height of several thousand feet, except immediately after a heavy downpour, when the air is washed clean.

Bacteria are present in all natural as well as in drinking water that has not been purified or bailed. A large number of bacteria live in the soil, down to a depth of several feet, and they are particularly abundant in faeces and sewage. Thus, living bacteria are always present on the surface of our bodies and on everything around us, but they are seldom found inside the tissues of healthy plants and animals.

Since most kinds of bacteria contain no chlorophyll, they cannot use light energy and Synthesize their food. They have to get their food in other ways, mostly ready-made by other living things. Like plants, it can only take in dissolved food. A majority get their supply from dead remains of other organisms.

Bacteria reproduce by dividing into two, and these new individuals grow so quickly that they are ready to divide again in about half an hour. Hence, in ten hours, under the most favorable conditions, a single bacterium can produce over a million bacteria. That is one reason for it being so difficult to ensure any object is completely free from any kind of living organisms. In addition, some forms of bacteria have a waxy envelope outside their cell wall and are thus more difficult to kill.

Few bacteria can long survive a temperature above 80°C in the presence of moisture. Hence, when food items are boiled, nearly all the bacteria present is killed. Pasteurization is a milder heat treatment that destroys the bacteria in milk.

The rate of multiplication of bacteria is greatly slowed down at temperatures below 10°C. This means that food will remain unaffected by bacteria in a refrigerator.

Drying is also another method of preserving food and this dehydration of foodstuff prevents bacteria from growing and multiplying as there is insufficientmoisture.

Summary: Bacteria are tiny colorless cell that cannot be seen with the naked eye. They are found everywhere in the atmosphere, in our water as well as in the soil. However, they are seldom found inside the tissues of plants and animals. They are unable to produce their own food and so they rely on other living things. Their reproduction process is through division of cells and this hap- pens very quickly, making it difficult to kill them. However, most bacteria are unable to survive a high temperature in water. The reproduction process is also slowed down when it is extremely cold. Dehydration of foodstuffs will also stop the multiplication process as there is insufficient moisture for the bacteria to grow.