Bacteria

They are in you yogurt, on your sponge, inside you nose, and on your skin! They are everywhere!

Bacteria was discovered in the 1600’s by Leeuwenhoek by using a microscope.

Bacteria Characteristics: Single celled Cell wall present Genetic Material/DNA is circular Prokaryotic (Genetic material is not contained inside a nucleus) No Mitochondria No Golgi Body

Characteristics continued….. They have a flagella (A whip-like structure that propels or moves the cell) Size ranges between 0.5 to 0.1 micrometer (That is one millionth of a meter!!!)

Three basic Shapes of Bacteria Spherical Rod-like Spiral

How do they eat?? Autotrophs: Make their own food by capturing sunlight or decomposing/using chemicals from their environment. Heterotrophs: Consume other organisms (Leaves, milk, meat) MOST need oxygen (respiration) to break down food.

Reproduction Bacteria reproduce frequently if the temperature and conditions are favorable. They reproduce asexually through binary fission (One cell splits (divides) to for two IDENTICAL cells.)

Asexual Reproduction They reproduce asexually through binary fission (One cell divides to form two identical cells.) ONE parent produces offspring that are IDENTICAL to the parent. Each new cell gets its own copy of genetic material.

Sexual reproduction Two parents combine genetic material to produce a new organism that is different from each parent. Conjugation-1 bacteria cell transfers genetic material to another through a thread-like bridge.

Endospores If environmental conditions are unfavorable for bacterial growth they form endospores. When conditions become favorable they grow and multiply.

Endospores Small, round, thick-walled resting cells Contatins genetic information and cytoplasm Resists freezing, heating, and drying Can survive for years

Why is bacteria important??? Oxygen Food production Environmental Recycling Environmental Clean-up Health and Medicine

Oxygen Bacteria make qxygen that we breathe by using the sun’s energy. Millions of years ago bacteria produced some of the Earth’s first oxygen.

Food production Some bacteria help produce pickles, cheese, yogurt, sourdough bread, and sour cream. Other bacteria make food spoil (go bad).

Environmental recycling Some bacteria (decomposers) live in the soil and break down chemicals and dead organisms. They break down items into useful chemical and nutrients for other organisms to use. Examples: Nitrogen fixing bacteria on bean roots make nitrogen into a usable form for plants.

Environmental Clean-up Some bacteria clean Earth and water after iul spills and by eating the oil.

Health and medicine Bacteria living in your body help keep you healthy and others help your body digest food. Some bacteria also used to make medicines such as insulin and penicillin.