1. Bacteria
By Mr. Frost
P1 – 6
P3 - 7

2. What are Bacteria? (or… what is a bacterium?)
Single Celled living organism with NO NUCLEUS
Called Prokaryotes
Pro – before
Karyon – nucleus
The simplest forms of life are prokaryotes.
Earth’s first cells were prokaryotes

3. Prokaryote vs. Eukaryote
DNA - Floats loosely in Prokaryote (Bacteria)
DNA is enclosed within and protected by Nucleus in Eukaryote (Non-Bacteria)

4. Bacterial Shapes Bacteria are classified by shape into 3 Groups
Singular / Plural
Bacillus / Bacilli: Rod
Spirillum / Spirilla: Spiral
Coccus / Cocci: Spherical

5. Bacterial Grouping or Arrangement
Paired: diplo
Chains: strepto
Grape-like clusters: staphylo

6. Bacteria are Ubiquitous
Prokaryotes are Earth’s most abundant life forms…. They are Everywhere.
They can survive in many environments.
They can get energy from many different sources.

7. 7 Major Structures Capsule: Keeps cell moist & sticky
Cell wall: Maintains cell shape
Ribosomes: Where Proteins are made
Nucleoid: “Ring” of DNA
Flagella: Propels cell through liquid
Pili: proteins to attach to other bacteria
Cytoplasm: Clear thick jelly-like substance in a cell that holds the contents

8. How they get Energy 1 Some Bacteria are Photosynthetic
Get Energy from the Sun
Autotrophs: Self Feeding / Producers: Produce Sugar

9. How they get Energy 2 Some Bacteria are Chemosynthetic
Get their energy from chemicals / NO SUN NEEDED
Autotrophs: Self Feeding / Producers: Produce Sugar
YouTube!

10. How they get Energy 3
Decomposers: Some Bacteria break down dead organisms. They secrete digestive enzymes then absorb some of the digested material, leaving much of it in the soil or water for other organisms.
Heterotrophs: Other Eaters / Consumers

11. How they Reproduce Bacteria Usually reproduce Asexually
This means there is no exchange of DNA.
A single bacterium can reproduce on its own.
The process is known as Binary Fission
Fusion = join together
Fission = to break into parts

12. Binary Fission A mature cell first copies its DNA.
Then the cell splits into 2 genetically identical cells.
These are called “offspring” cells or “daughter cells”

13. How they Reproduce Bacteria Occasionally reproduce Sexually
This means they exchange DNA w/another bact.
Requires 2 bacteria
Two Steps: Conjugation followed by Binary Fission
Conjugation is exchange of DNA
Binary Fission is cell division

14. Conjugation This is the first step of sexual reproduction.
Note that this changes the DNA makeup of the Recipient Bacterium.

15. Binary Fission This is the second step of sexual reproduction.
We Already covered this.
The new genetic makeup is copied and passed down to the daughter cells.

16. Bacterial Locomotion
Locomotion is the process of moving from one place to another.
Bacteria use 2 primary methods.
Flagella (Singular=Flagellum)
Cilia (Singular=Cilium)
YouTube Flagella & Cillia

17. Bacterial Locomotion
Flagella: “Long whiplike structures” that actually spin like the rotor of a boat or propeller of a plane.

18. Bacterial Locomotion
Cilia: Short hairlike structures that “do the wave,” beating in symphony to propel the bacteria.