1. Structure and Function
Bacteria
Structure and Function

2. Prokaryotic & Eukaryotic Cells

3. Characteristics of Bacteria

4. Bacterial Structure Microscopic prokaryotes
No nucleus or membrane-bound organelles
Contain ribosomes
Single, circular chromosome in nucleoid region

5. Bacterial Cell

6. Protection Cell Wall made of Peptidoglycan
May have a sticky coating called the Capsule for attachment to host or other bacteria

7. Sticky Bacterial Capsule

8. Bacterial Structure Have small rings of DNA called Plasmids
Unicellular
Small in size (0.5 to 2μm)
PLASMIDS

10. Bacterial Structure
Infoldings of cell membrane carry on photosynthesis & cellular respiration
Infoldings called Mesosomes

11. Mesosomes
MESOSOME

12. Bacterial Structure Most grow best at pH of 6.5 to 7.0
Many act as decomposers recycling nutrients
Some cause disease

13. Flagella Bacteria that are motile have appendages called flagella
Attached by Basal Body
A bacteria can have one or many flagella

15. Flagella Made of Flagellin Monotrichous: 1 flagella
Used for Classification
Monotrichous: 1 flagella
Lophotrichous: tuft at one end
Amphitrichous: tuft at both ends
Peritrichous: all around bacteria

16. Monotrichous
Lophotrichous
Amphitrichous
Peritrichous

17. What is this type of bacteria ?
Question:
What is this type of bacteria ?

18. Pili Short protein appendages Smaller than flagella
Adhere bacteria to surfaces
Used in conjugation for Exchange of genetic information
Aid Flotation by increasing buoyancy

19. Pili in Conjugation

20. Reproduction Bacteria reproduce asexually by binary fission
Single chromosome replicates & then cell divides
Rapid
All new cells identical (clones)

21. Cellular organism copies it’s genetic information then splits into two identical daughter cells