the kingdom of bacteria

Bacteria are found everywhere, they are on the table you sit at and in the air you breathe in. Some are harmful and can cause disease, but many help us survive, some even help us digest our food. There are about a trillion human cells in each human body, making us who we are. But there are about 10 trillion bacterial cells living in and on our bodies at any moment in our lives! This means you could say we are only about 9 percent human 

Bacteria are microscopic, unicellular organisms without a nucleus. They have cell walls and cell membranes. Bacteria reproduce through division. This means that a bacterium simply splits itself into two new individuals when it reproduces. Bacteria can be shaped like rods, spheres (ball-shaped) and spirals. Bacterial cells are much smaller than animal or plant cells.

Bacteria can be useful. Some groups of bacteria can feed on and remove dead organisms. Other species of bacteria are used in the production of food like yoghurt and cheese. Some are even used to clean water in wastewater treatment.

Bacteria can also be harmful. They can cause food poisoning and other diseases like pneumonia (an infection in the lungs) and cholera. Cholera is caused by bacteria in dirty drinking water.