1. Lecturer: Pn Aslizah Bt Mohd Aris 06-4832168 / 016-7377621
Diploma in Microbiology MIC102 CHAPTER 1 Cell Theory- Structure and Function (PROKARYOTE)
Lecturer: Pn Aslizah Bt Mohd Aris /

2. What is Cell Biology?
is an academic discipline which studies the physiological properties of cells, as well as their behaviours, interactions, and environment
this is done both on a microscopic and molecular level.
researches both single-celled organisms like bacteria and specialized cells in multicellular organisms like humans. 2

3. SYLLABUS CONTENT Cell Theory- Structure and Function
Chap 1
Cell Theory- Structure and Function
- Prokaryotic cell - Eukaryotic cell- Cell membrane
Chap 2
Movement In And Out Of Cell
- Diffusion, Osmosis, Active Transport, Endocytosis, Phagocytosis, Pinocytosis, Excocytosis
Chap 3
Reproduction of Prokaryotic cell-
-Binary fission and conjugation
Chap 4
Reproduction of eukaryotic cell / Cell division
- Chromosome morphology and function, The cell cycle and mitosis, Meiosis and gametogenesis

4. Overview: The Fundamental Units of Life
The cell is the simplest collection of matter that can live.
All organisms are made of cell.
Cell structure is correlated to cellular function.
All cells are related by their descent from earlier cells.
For the Discovery Video Cells, go to Animation and Video Files.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

5. How do cellular components cooperate to help the cell function?
Figure 6.1 How do cellular components cooperate to help the cell function?

6. What is a Cell? Basic structural and functional unit of all organisms;
they may exist as independent units of life (as in
monads) or may form colonies or tissues as in higher
plants and animals.
General characteristic of cells is their microscopic size.
Typical size-Eukaryotic cell: µm in diameter
-Prokaryotic cell: 1-10 µm in diameter

7. Cell Theory
1665: Robert Hooke, 1st observed cells, naming the shapes as “cork cellulae” (Latin= “small rooms”).
Anton van Leeuwenhoek, 1st observed live cells, which he termed as “tiny animalcules”.
1839: Theodor Schwann reported that all animal tissues also consist of individual cells.
Thus was born “CELL THEORY”

8. Cell Theory: The Principle
Three (3) principles involves:
All organisms are composed of one or more cells, and the life processes of metabolism and heredity occur within these cells.
Cells are the smallest living things, the basic units of organization of all organisms.
Cell arises only by division of previously existing cell.

9. Basic Cellular Architectures:
Prokaryotic cells; refer to the presence
Eukaryotic cells @ absence of the cell structures.
DOMAIN
KINGDOM
Prokaryotic cells
Archaea
Bacteria
Eukaryotic cells
Plantae
Fungi
Animalia
Protista

10. Prokaryotic Cells
Bacteria and archaea are prokaryotes. The figure (right) reviews the structure of a typical prokaryotic cell.
Bacterium (plural, bacteria):
single-celled organism with no nucleus and little or no intracellular compartmentalization; a prokaryote.
Eubacterium (plural, eubacteria):
member of one of the two main groups of prokaryotes, the other being archaebacteria; includes most present-day bacteria and cyanobacteria.
Cyanobacterium (plural, cyanobacteria):
bacteria that have chlorophyll and can carry out photosynthesis; considered by the endosymbiont theory to be the progenitor of eukaryotic chloroplats. 10

11. The Structure of a Prokaryotic Cell

12. simplest organisms.
small, consisting of cytoplasm surrounded by a plasma membrane and encased within a rigid cell wall, lack complex interior organization.
nucleoid is visible as a dense central region segregated from the cytoplasm.
do contain complex structures, like ribosome to carry out protein synthesis.
cell membrane carries out some of the function s organelles perform in eukaryotic cells.

13. The Cell Wall
Strength of the cell comes primarily from its rigid cell wall, protects the cell, maintain its shape & prevent excessive uptake and loss of water.
Prevents osmotic lysis
Made of peptidoglycan (in bacteria)
Figure 4.6

14. Peptidoglycan Polymer of disaccharide: N-acetylglucosamine (NAG)
N-acetylmuramic acid (NAM)
Figure 4.12

15. Peptidoglycan in Gram-Positive Bacteria
Linked by polypeptides
Figure 4.13a

16. Gram-Positive Bacterial Cell Wall
Figure 4.13b

17. Gram-Negative Bacterial Cell Wall
Figure 4.13c

18. Gram-positive Cell Wall
Gram-negative Cell Wall
Thick peptidoglycan
Teichoic acids
Thin peptidoglycan
Outer membrane
Periplasmic space
Figure 4.13b–c

19. The Plasma Membrane
Figure 4.14a

20. The Plasma Membrane Phospholipid bilayer Peripheral proteins
Integral proteins
Transmembrane
Proteins
Figure 4.14b

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

22. Cytoplasm
The substance inside the plasma membrane
Figure 4.6

23. The Nucleoid Bacterial chromosome Contains genetic information
Figure 4.6

24. Ribosomes
Sites of protein synthesis
Figure 4.6

25. The Prokaryotic Ribosome
Protein synthesis
70S
50S + 30S subunits
Figure 4.19

26. Inclusions Phosphate reserves Metachromatic granules (volutin)
Energy reserves
Ribulose 1,5- diphosphate carboxylase for CO2 fixation
Protein-covered cylinders
Iron oxide (destroys H2O2)
Metachromatic granules (volutin)
Polysaccharide granules
Lipid inclusions
Sulfur granules
Carboxysomes
Gas vacuoles
Magnetosomes

27. Other characteristics
most have no membrane bounded organelles, which characterize the eukaryotes.
lack of the elaborate cytoskeleton found in eukaryotes.
The DNA, enzymes, and other cytoplasmic constituents have access to all parts of the cell.
cell contain no membrane bounded organelles;
whole prokaryotes operate as a single unit rxns, not compartmentalized as in eukaryotes.
“one room cabin in which eating, sleeping and watching TV is all occur”.

28. External Structures to the Cell Wall
Glycocalyx.
Flagella
Axial filaments
Fimbriae and pili.

29. Glycocalyx Outside cell wall Slime layer: unorganized and loose
Usually sticky
Capsule: neatly organized
Slime layer: unorganized and loose
Extracellular polysaccharide allows cell to attach
Capsules prevent phagocytosis
Figure 24.12

30. The Structure of a Prokaryotic Flagellum
outside cell wall
made of chains of flagellin
attached to a protein hook
anchored to the wall and membrane by the basal body
Figure 4.8b

31. Arrangements of Bacterial Flagella

32. Axial Filaments Also called endoflagella In spirochetes
Anchored at one end of a cell
Rotation causes cell to move
Figure 4.10a

33. Fimbriae and Pili
Fimbriae allow attachment
Figure 4.11

34. Fimbriae and Pili
may have hairlike growth (called pili) on the outside of the cell).
Facilitate transfer of DNA from one cell to another
Gliding motility
Twitching motility

35. LETS WATCH MOVIE !!!
Prokaryotic Cell Structure and Function

36. ACTIVITY
example:
In pair discuss the function of bacteria/prokaryote structure and try to produce 1 table consist of the function of each structure
STRUCTURES
FUNCTIONS
Flagellum
Movement…
Pilus

37. See u tomorrow..thank you….