1. Kingdoms: Archaebacteria & Eubacteria

2. The Basic Bacteria Cell
Bacteria cells have a simple structure:
Cell Wall
Cell Membrane
Cytoplasm
Ribosomes
Genetic Material: DNA
Flagella: a whip-like structure for movement
THINK! - How is bacteria cell different from a plant/animal cell?
Bacteria cells have no nucleus or organelles (other than ribosomes)

3. Two Kingdoms of Bacteria
Archaebacteria
“Ancient Bacteria”
Cell Walls do not have peptidoglycan (sugar)
Live in EXTREME environments
Hot springs
Very salty waters
Sewage
Eubacteria
“New Bacteria”
Cell walls contain peptidoglycan (sugar)
Live almost anywhere
Soil
Inside organisms

4. Bacteria Structure: Shapes
Bacteria cells have one of three basic shapes: rod shaped, spherical, & spiral.
TRY THIS!
Use a compound microscope to observe the structure of these different bacteria!
Bacillus – rods
“Bars”
Coccus – spheres
“Circles”
Spirillum - spirals

5. How fast can bacteria multiply?
Watch This!
Watch how many bacteria there are after 24 hrs!
Division Time_Prokaryotic Cells
Under ideal conditions, bacteria can reproduce as often as every 20 minutes!
Calculate how many bacteria would there be after 3 hours.
512

6. Reproduction in Bacteria
Binary Fission:
This is where one cell divides to form 2 identical cells.
The process involves only 1 parent. Therefore, it is considered asexual reproduction.
Steps:
DNA replicates
Cell Splits

7. Obtaining Energy Autotrophs Heterotrophs
These bacteria make their own food
Some get energy from the sun
Some get energy from chemicals
Heterotrophs
These bacteria that seek out their food
They feed off of milk, meat, and decaying material
THINK! - Do you think all bacteria need oxygen to survive?
Aerobes: Need oxygen VS. Anaerobes: DO NOT need oxygen

8. Where Can We Find Bacteria?
TRY THIS!
Think of 4 objects in this classroom you think might contain a lot of bacteria.
We will swab these areas and allow the bacteria to grow on agar plates.
After 24 and 48 hours we will be able to observe how much bacteria is found in these locations!

9. Bacteria In Nature TRY THIS! Bacteria can act as “nature’s recyclers”:
Observe these two pieces of lettuce. What do you notice?
Bacteria can act as “nature’s recyclers”:
Bacteria in soil break down dead trees, leaves, and animals
These bacteria are known as decomposers

10. Bacteria In Nature Bacteria can cause diseases such as:
Tooth decay – Streptococcus mutans
Lyme disease – Borrelia burgdorferi
Tetanus – Clostridium tetani
Tuberculosis – Mycobacterium tuberculosis
Salmonella – Salmonella enteritidis
Pneumonia – Streptococcus pneumoniae
THINK! - What can doctors prescribe to kill growing bacteria?
Antibiotics

11. …But antibiotics don’t always work
This is due to the fact that bacteria can rapidly mutate and become resistant to antibiotics.
Click on the first video – Shows a true life example of a hog farmer that was infected with resistant bacteria.
The mutated ones survive after the antibiotics are gone.
Antibiotics attack and kill off bacteria without the mutation.
They reproduce, passing along the mutation to their offspring.
Eventually there are more antibiotic- resistant bacteria than non-resistant.

12. Bacteria in Nature
Humans use certain bacteria to manufacture food products such as:
Cheese
Yogurt
Sour cream
Pickles
Sauerkraut
Apple Cider
TRY THIS!
Use a compound microscope to observe the natural bacteria found in yogurt!
OR – Watch this clip from United Streaming on “Bacteria in Society”