1. Bacteria

2. The Bacteria Cell
Not discovered until 1600 by our buddy Anton van Leeuwenhoek
Bacteria are prokaryotes (have no nucleus)
Their genetic material in their cells is not contained in a nucleus
Bacteria are living organisms because they use energy, grow, and respond to their surroundings.

3. Bacteria Structure
ALL are prokaryotes
All are unicellular
Some are Autotrophs & Some are Heterotrophs
Bacterial cells are surrounded by a rigid cell wall. Inside the cell wall is the membrane
The inside is filled with cytoplasm, ribosomes and genetic protein
May have flagellum that helps a cell to move

4. Bacteria Cell Shape and Size
One of three basic shapes
Spherical
Rodlike
Spiral
It is the chemical make up of the cell that determines its shape
The shape helps scientist determine type
Cell Size
Size vary greatly; average is .5 to 1 micrometer
A micrometeri(um) is one millionth of a meter

5. I’m Hungry (Obtaining Food and Energy)
Bacteria must have a source of food and a way of breaking down the food to release energy
Some bacteria are autotrophs making their own food through the process of photosynthesis or using chemical substances in their environment

6. I’m Still Hungry Other bacteria are heterotrophs
They must consume other organisms or the food that other organisms make
May consume a variety of foods – from milk to meat, which you might also eat, to the decaying leaves on forest floor

7. Respiration
The process of breaking down food to release its energy is called respiration
Organic compounds + Oxygen →
Carbon dioxide + Water + Energy

8. Reproduction
When bacteria have plenty of food, the right temperature, and other suitable conditions, they thrive and reproduce frequently
Two Type
Asexual Reproduction
Binary fission is a form of asexual reproduce
Sexual Reproduction
Conjugation; transfers some of its genetic material into another bacterium through thread-like bridge

9. What Occurs in the Process
Asexual Reproduction
Sexual Reproduction
Name of Process
Binary Fission
Conjugation
Number of Parents 1 2
What Occurs in the Process
The cell duplicates its genetic material, then divides into 2 separate cells
One bacterium transfers some genetic material to another through threadlike bridge
Result of Process
New cells identical to parent
Bacteria are genetically different from parent

10. Endospore Formation
When conditions in the environment become unfavorable for growth some bacteria form endospores
Endospores are small rounded, thick-walled resting cell that form inside a bacteria cell containing the cell’s genetic material and some cytoplasm
Can resist freezing, heating and drying they can survive for many years

11. The Role of Bacteria in Nature
Bacteria are involved in:
O2 production
food production,
environmental recycling and cleanup,
Medicine production

12. Oxygen Production
Scientist credit autotrophic bacteria for making our earth habitable for life.
The autotrophic bacteia use the sun’s energy to produce food and a waste product is oxygen

13. Food Production
Can help create food such as sourdough bread, yogurt, sour cream, and cheeses
Can also cause food to spoil
Refrigerating and heating help slow down spoilage
Pasteurization (Louis Pasteur) is heating food to a temperature that is high enough to kill most harmful bacteria with changing the taste.

14. Environmental Recycling
Bacteria are the “decomposers” –organism that break down large chemicals in dead organisms into small chemicals
Return basic chemicals back to the environment to be used again
Nitrogen-fixing bacteria help plants by converting nitrogen gas from the air into nitrogen products the plants can use.

15. Cleanup Crew
Cup of oil anyone? Some bacteria can break down oil converting poisonous chemicals into harmless substances

16. What role do bacterial decomposers play in the environment?
Bacterial decomposer play a very important role in the environment by breaking down dead organism into basic chemicals that other organism can reuse.

17. Health and Medicine In your digestive system Make vitamins
Prevent harmful bacteria from attaching to your intestines
genetically altered bacteria help make scientist produce insulin to help people with diabetes