Bacteria (one of them is a bacterium) are very small organisms (living things). They are so tiny they can only be seen through a microscope. Bacteria are made up of one cell, so they are a kind of unicellular organism.
Our planet is chock full of bacteria. There are typically 40 million bacterial cells in a gram of soil and a million bacterial cells in a millilitre of fresh water. In total there are approximately five nonillion bacteria on Earth and the total biomass of bacteria is estimated to be equal to that of plants.
It is estimated that 500 to 100,000 different species of bacteria live in the human body and there are about ten times as many bacteria as human cells in the body. So you’ve got about 1000 trillion bacteria in and on you right now!
Bacteria can divide as often as once every 20 minutes.
Amazingly, if a single bacterium had infinite food and space, after reproducing for a mere 48 hours the resultant colony would weigh 4000 times the mass of the Earth! The good thing is that this does not happen since nutrients are always limiting and they are also limited by space and often harsh environmental conditions. Read more here.
Tags: Microbiology, Science, Video
