1. Functional Anatomy of Prokaryotic and Eukaryotic Cells4
Functional Anatomy of Prokaryotic and Eukaryotic Cells

2. Prokaryotic Cells Comparing prokaryotic and eukaryotic cells
Prokaryote comes from the Greek words for prenucleus.
Eukaryote comes from the Greek words for true nucleus.

3. Prokaryote Eukaryote One circular chromosome, not in a membrane
No histones
No organelles
Peptidoglycan cell walls
Binary fission
Paired chromosomes, in nuclear membrane
Histones
Organelles
Polysaccharide cell walls
Mitotic spindle

4. Basic Prokaryote (Bacterial) Cell Shapes
Average size: µm  µm
Basic shapes:
Spirillum
Bacillus
Diplococci
Streptococci
Spirochete
Coccobacillus

5. Figure Overview

6. Figure 4.1a

7. Figure 4.1d

8. Figure Overview

9. Figure 4.2a–b

10. Figure 4.2c

11. Bacillus anthracis
Figure 4.3

12. Figure Overview

13. Most bacteria are monomorphic A few are pleomorphic
Unusual shapes
Star-shaped Stella
Square Haloarcula
Most bacteria are monomorphic
A few are pleomorphic
Figure 4.5

14. Glycocalyx – “Sugar Coat”
Outside cell wall
Usually sticky
A capsule is neatly organized
A slime layer is unorganized and loose
Extracellular polysaccharide (EPS) allows cell to attach
Capsules prevent phagocytosis
Figure 4.6a–b

15. Figure Overview

16. Flagella Outside cell wall Made of chains of flagellin
Attached to a protein hook
Anchored to the wall and membrane by the basal body
Figure 4.8a

17. Flagella Arrangement
Figure 4.7

18. Figure 4.8b

19. Motile Cells Rotate flagella to run or tumble
Move toward or away from stimuli (taxis)

20. Motile Cells
Figure 4.9

21. Motile Cells
PLAY
Animation: Bacterial Motility
Figures 4.9a, 4.23d

22. Axial Filaments Endoflagella In spirochetes
Anchored at one end of a cell
Rotation causes cell to move
Figure 4.10a

23. Fimbriae allow attachment
Pili are used to transfer DNA from one cell to another
Figure 4.11

24. Cell Wall Prevents osmotic lysis Made of peptidoglycan (in bacteria)
Figure 4.6a–b

25. Figure 4.6a

26. Peptidoglycan
Polymer of disaccharide N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM)
Linked by polypeptides
Figure 4.13a

27. Figure 4.13b–c

28. Gram-Positive Gram-Negative Cell Walls Cell Walls
Thick peptidoglycan
In acid-fast cells, contains mycolic acid
Thin peptidoglycan
Outer membrane
No mycolic acid

29. Gram Gram -
UN 4.2

30. Gram-Negative Outer Membrane
Lipopolysaccharides, lipoproteins, phospholipids
Forms the periplasm between the outer membrane and the plasma membrane.
Protection from phagocytes, complement, and antibiotics

31. Gram Stain Mechanism Crystal violet-iodine crystals form in cell.
Gram-positive
Alcohol dehydrates peptidoglycan
CV-I crystals do not leave
Gram-negative
Alcohol dissolves outer membrane and leaves holes in peptidoglycan.
CV-I washes out

32. Damage to Cell Walls Lysozyme digests disaccharide in peptidoglycan.
Penicillin inhibits peptide bridges in peptidoglycan.
Protoplast is a wall-less cell.
Protoplasts and spheroplasts are susceptible to osmotic lysis.

33. Plasma Membrane
Figure 4.14a

34. Plasma Membrane Phospholipid bilayer Peripheral proteins
Integral proteins
Figure 4.14b

35. Fluid Mosaic Model Membrane is as viscous as olive oil.
Proteins move to function.
Phospholipids rotate and move laterally.
Figure 4.14b

36. Figure 4.14c

37. Plasma Membrane
Selective permeability allows passage of some molecules
Enzymes for ATP production
Photosynthetic pigments on foldings called chromatophores or thylakoids

38. Movement Across Membranes
Simple diffusion: Movement of a solute from an area of high concentration to an area of low concentration.
Facilitative diffusion: Solute combines with a transporter protein in the membrane.

39. Movement Across Membranes
Figure 4.17

40. Movement Across Membranes
Osmosis: The movement of water across a selectively permeable membrane from an area of high water concentration to an area of lower water concentration.
Osmotic pressure: The pressure needed to stop the movement of water across the membrane.
Figure 4.18a

41. Movement Across Membranes
Figure 4.18a–b

42. Figure 4.18c–e

43. Movement Across Membranes
Active transport of substances requires a transporter protein and ATP.
PLAY
Animation: Membrane Transport

44. Cytoplasm Cytoplasm is the substance inside the plasma membrane.
Figure 4.6a–b

45. Nuclear Area Nuclear area (nucleoid) Bacterial chromosome Plasmids
Figure 4.6a–b

46. Ribosomes
Figure 4.6a–b

47. Ribosomes
Figure 4.19

48. Inclusions
Figure 4.20

49. Endospores Resting cells Resistant to desiccation, heat, chemicals
Bacillus, Clostridium
Sporulation: Endospore formation
Germination: Return to vegetative state

50. Figure 4.21b

51. Figure 4.21a, step 1

52. Figure 4.21a, step 2

53. Figure 4.21a, step 3

54. Figure 4.21a, step 4

55. Figure 4.21a, step 5

56. Figure 4.21a, step 6

57. Figure Overview