They eat decomposing wastes algi fungi and other things such as dead skin cells and hair. And they use extra-cellular digestion where the bacterium releases enzymes that break down the food so they can pass through the cell, they have no mouth so they use a process called osmosis to break down and digest there foods that's just to take to eat it is like this
Bacteria do not have a mouth. They make proteins called enzymes inside the cell and these travel thru the cell wall into the surrounding medium. The enzymes chop the food into tiny subunits which then come into the bacteria cell by osmosis or active transport. Active transport is the process by which the cell grabs a molecule of glucose or other food and pulls it in thru the cell wall. Many specialized proteins and other molecules made by the bacterium are involved in this active transport process. Perhaps someday you can figure out ways to study the mechanisms of active transport.
The process by which the enzyme chops the food into subunits is also very complex and specific and usually requires one molecule of water for each split. If water is consumed, the chopping process is called hydrolysis (splitting by water).
The enzyme which is able to hydrolyse lactose (milk sugar) will not fit into a protein molecule the right way to be able to hydrolyze protein. Further, lactase (an enzyme able to hydrolyse lactose) will not be able to fit into a starch molecule to split it. Thus, if a bacterium is going to eat many kinds of foods, it must have many kinds of hydrolases because enzymes do very specific jobs.
Some bacteria have many kinds of enzymes and can eat many kinds of foods. Other bacteria have few enzymes and are able to digest very few kinds of food. Bacteria which do not have the correct enzymes can still live off a given food by growing where other bacteria have ready broken the food down. This is similar to a gull eating bits of sealion meat left by a shark that killed the sealion. Thus, in food processing we might used a "mixed culture" and get an especially delightfully tasting and digestible food. This website has some very interesting experiments like this for the home fermentation of special foods.
We have just learned that bacteria differ in the foods they are able to digest and that is one of the ways we can tell them apart. For example some species of Clostridium are able to digest carbohydrates and make alcohols and very smelly organic acids but can't digest proteins. Other Clostridium species can digest proteins and cause serious problems in human wounds, but do not digest carbohydrates. A few Clostridium species can digest proteins and carbohydrates. Thus, trying to grow an unknown Clostrium species upon separate carbohydrate and protein media can help us identify the unknown species.
Why would anyone want to know the name of a Clostridium? Simple, some Clostridium species are harmless and some are human pathogens (causing disease in humans). Suppose a doctor found a Clostridium in a deep wound in your body, you would suddenly be very interested wouldn't you. Or suppose you want a career helping other people; you might want to learn such thing so you could be a bacteriologist or doctor. Or you might want to study the bacteria which can ferment coarse seeds like soybeans to make a fine, tasty cheese-like food to add zest to the diets of all nations able to grow or buy soybeans.
and inappropriate answers like
"they open there mouth and eat" as a teacher to me it sounds stupid
no inless you eat fatty food with bacteria on to it
they produce by photosynthesis and chemosynthesis. They also eat other bacteria
Only by eating other food would foxes eat bacteria.
they dont eat...theyre bacteria they dont eat...theyre bacteria
by raping other cells
Bacteria get their energy from the food they eat.
Bacteria aren't a major part of a mouse's diet, but, like any other animal, they consume the bacteria that are on their food every time they eat.
For the same reason that you do; to gain food (substenance) and energy with which to survive.
Grasshoppers eat bacteria all the time as it covers all of their food. It also covers their body and is consumed when they groom themselves.
No, I spray my food with antiseptic before I eat it. And bleach.
Bacteria land on it and starts to eat it
they eat algi and bacteria off of whatever they are on