BACTERIA   KINGDOM

What are bacteria?

Bacteria are the smallest of living organism. We can't see them without a microscope because they are so small.

They are everywhere around us: in the air, on our skin, in our bodies, in the ground, in the ocean, in clouds, on living things and also on dead things.

Bacteria are microorganism made of only one cell.

Most bacteria are very helpful to humans and are very useful for the industry (to transform milk in cheese or yoghourt,  for petroleum ...)

But some bacteria cause health problems in animals and plants. These bacteria are called pathogens. We use antibiotics to fight against them.


Classification

We can clasify bacteria depending on many factors: Shape

Size

Movement

Feedig system

...

Depending on their morphology and shape bacteria are divided in:

1. Coccus: Spherical shapep like little balls. They can be found alone, in pairs, in clumps or in long chains
2. Bacillus: Straight shape like a stick
3. Coccobacillus: Between a sphere and a rod
4. Spirillus and spirochete: Spiral shaped like a corkscrew 
5. Filamentous: Elongated shape

Vital Function

Bacteria exist in nature as individual cells.
Bacteria usually live in colonies. Some bacteria work together in groups.

BACTERIAL COLONIES

The mains functions of bacteria are:

• Collect enough nutrients to survive.
• Reproduce. Bacteria reproduce quickly. Bacteria can reproduce about once every 20 minutes. The process of reproduction called binary fission.

Parts of the Bacteria Cell 

Bacteria are very simple cells.

They don’t have a nucleus but they have DNA in an area called the nucleoid. 

They have some envelopes as protection: capsule and cell wall.

They have cell membrane to contain the cytoplasm and to control the transit in and outside the cell.

They don't have specialized organelles, just ribosomes. 

Sometimes they have elements for movement like pilus or Flagellum.


Fun Facts


There are 10,000 known species of bacteria. 

Bacteria are the most abundant organism in the world. 

There are more bacteria in the mouth than people in the world 

Bacteria can survive in extrem conditions including deep areas of the Earth's crust, in the space and in radioactive waste. 

There are around as many bacteria cells in a human body as there are human cells. 

Some bacteria have chemicals that can generate light. This is called bioluminescence.

THE END