1. CHARACTERISTICS OF PROKARYOTIC AND EUKARYOTIC CELLS
CHAPTER 4

2. Cellular Characteristics

3. Cellular Characteristics
2 Domains, then Phyla
1 Domain, 4 kingdoms, then Phyla

4. Prokaryotic Cells Sizes 0.5 - 2µm (average) Shapes Cocci Bacilli
Spirals

5. Prokaryotic Cell Arrangements
Pairs
Diplo-
Tetrads
Chains
Strepto-
Clusters
Staphylo-

6. Typical Prokaryotic Cell

7. Gram Positive Cell Walls
Peptidoglycan
Thick layer
Physical strength
Teichoic Acids
Molecular transport
Viral attachments

8. Gram Negative Cell Walls
Outer Membrane
LPS components (Endotoxin)
Periplasmic space
Digestive Enzymes
Protein pumps
Chemical resistance
Thin peptidoglycan layer

9. Other Cell Walls Acid Fast Cell Wall Mycolic acid or other lipid
Gram positive structure
Cell Wall Deficient bacteria

10. Prokaryotic Plasma Membrane
Fluid Mosaic
Proteins embedded in lipid
Phospholipids
Inner hydrophobic region
Outer hydrophilic
Chemical movement
Small
Uncharged

11. Prokaryotic Plasma Membrane

12. Internal structures Cytoplasm Watery medium Enzymes Cytoskeleton
Ribosomes
70S
Nuclear region

13. Endospores Stasis versus vegetative state Medically significant genera
Resistances
Dipicolinic acid

14. External Prokaryotic Structures
Motility:
Flagellae
Axial filaments

15. Motility “Behaviors”

16. External Prokaryotic Structures
Attachment:
Pili
Conjugation pili
Fimbriae

17. Glycocalyx Capsule Attachment
May limit penetration of some substances such as antibiotics, disinfectants
Virulence factor
Slime Layer
Gliding substrate

18. Eukaryotic Cell Structure

19. Core Cellular Components
Plasma membrane
Cytoplasm
Nucleus
Ribosomes

20. Mitochondria and Chloroplasts

21. Mitochondria and Chloroplasts

22. Membranous Networks
Endoplasmic Reticulum
Rough
Smooth
Golgi apparatus

23. Eukaryotic Organelles/ Inclusions
Lysosomes
Peroxisomes
Vacuoles
Cytoskeleton

24. Motility
Flagella
Cilia
Pseudopods

25. Cell Wall components
Fungi
Plants
Protozoan pellicle

26. Endosymbiosis Evidence: DNA in Mt and chloroplasts 70S ribosomes
No mitosis
Two membranes

27. Eukaryotic/Prokaryotic symbiosis observed in today’s world (Protozoan termite inhabitant with internalized bacteria)

28. Movement across Membranes
Diffusion
Molecules move down a concentration gradient
Size and charge are factors
Osmosis
Water molecule movement

29. Active Transport Protein pumps span the membrane ATP energy required
Large charged molecules

30. Endo/Exocytosis Engulfment (Endocytosis) Eukaryotic activity
Protozoan cells
Phagocytic WBC
Extrusion (Exocytosis)