Presentation is loading. Please wait.

Presentation is loading. Please wait.

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation prepared by Christine L. Case Microbiology.

Similar presentations


Presentation on theme: "Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation prepared by Christine L. Case Microbiology."— Presentation transcript:

1 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation prepared by Christine L. Case Microbiology B.E Pruitt & Jane J. Stein AN INTRODUCTION EIGHTH EDITION TORTORA FUNKE CASE Chapter 4 Functional Anatomy of Prokaryotic and Eukaryotic Cells

2 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Prokaryotic Cells Comparing Prokaryotic and Eukaryotic Cells Prokaryote comes from the Greek words for prenucleus. Eukaryote comes from the Greek words for true nucleus. Learning objective: compare and contrast overall cell structure of prokaryotes and eukaryotes.

3 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cell membrane Cytoplasm One circular chromosome, not in a membrane No histones No organelles Peptidoglycan cell walls Binary fission ProkaryoteEukaryote Cell membrane Cytoplasm Paired chromosomes, in nuclear membrane Histones Organelles Polysaccharide cell walls Mitotic spindle

4 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Average size: µm µm (1 x m) Are unicellular and most multiply by binary fission Basic shapes: Learning objective: Identify the three basic shapes of bacteria. COCCUSBACILLUSSPIRAL

5 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Pairs: diplococci, diplobacilli Clusters: staphylococci Chains: streptococci, streptobacilli Arrangements

6 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Arrangements of cocci: Can be determined by division of planes.

7 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Arrangements of bacilli:

8 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Arrangements of spiral bacteria:

9 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Double- stranded helix formed by Bacillus subtilis. Bacillus cells often remain attached to each other, forming extended chains.

10 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Unusual shapes (Prokaryotes) Star-shaped Stella Square Haloarcula (halophilic archaea – salt-loving) Most bacteria are monomorphic (single shape) A few are pleomorphic (many shapes) Figure 4.5

11 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Learning objective: Describe the structure and function of the glycocalyx, flagella, axial filaments, fimbriae, and pili. Prokaryote cell

12 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Outside cell wall Usually sticky A capsule is neatly organized A slime layer is unorganized & loose glycocalyx Extracellular polysaccharide (EPS) allows cell to attach Capsules prevent phagocytosis Protects against dehydration or loss of nutrients. Glycocalyx Figure 4.6a, b

13 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Long filamentous appendages of a filament, hook, and basal body Outside cell wall Made of chains of flagellin Attached to a protein hook Anchored to the wall and membrane by the basal body Flagella Figure 4.8

14 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Flagella Arrangement Figure 4.7 Four arrangements of flagella:

15 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Rotate flagella to run or tumble Move toward or away from stimuli (positive and negative taxis) Flagella H proteins are antigens (e.g., E. coli O157:H7) Motile Cells

16 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Motile Cells Figure 4.9 A Proteus cell swarming may have peritrichous flagella. (from all sides)

17 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Endoflagella In spirochetes Anchored at one end of a cell Rotation causes cell to move Axial Filaments (endoflagellum) Figure 4.10a

18 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Fimbriae and Pili Are short, thin appendages Fimbriae of this E. Coli cell allow attachment (velcro). Cell is beginning to divide. Pili are used to transfer DNA from one cell to another Figure 4.11

19 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Prevents osmotic lysis (protects against changes in water pressure) Made of peptidoglycan (in bacteria = NAG+NAM+amino acids) – penicillin interferes with production of peptidoglycan Contributes to disease capability and site of action of some antibiotics. Cell Wall Figure 4.6a, b Learning objectives: Compare/contrast cell walls of gram-positive bacteria, gram-negative bacteria, archaea, and mycoplasmas. Differentiate between protoplast, spheroplast, and L form.

20 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Polymer of disaccharide N-acetylglucosamine (NAG) & N-acetylmuramic acid (NAM) Linked by polypeptides Peptidoglycan (murein) Figure 4.13a The small arrows denote where penicillin interferes with linkage of peptidoglycan rows.

21 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 4.13b, c Gram positive vs. gram negative cell walls

22 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Thick peptidoglycan Teichoic acids (alcohol+phosphate) In acid-fast cells, contains mycolic acid (waxy lipid) – allows them to be grouped into medically significant types. Gram-positive cell wallsGram-negative cell walls Thin peptidoglycan (subject to mechanical breakage) No teichoic acids Outer membrane: Evades phagocytosis Barrier to certain anti- biotics

23 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Teichoic acids: Lipoteichoic acid links to plasma membrane Wall teichoic acid links to peptidoglycan May regulate movement of cations (+ charge) Polysaccharides provide antigenic variation (identification) Gram-Positive cell walls Figure 4.13b

24 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Lipopolysaccharides, lipoproteins, phospholipids. Forms the periplasm between the outer membrane and the plasma membrane. Protection from phagocytes, complement (30+ liver proteins that protect host), antibiotics. O polysaccharide antigen, e.g., E. coli O157:H7. Lipid A is an endotoxin. Porins (proteins) form channels through membrane to pass other molecules Gram-Negative Outer Membrane

25 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Gram-Negative Outer Membrane Figure 4.13c

26 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Crystal violet-iodine (CV-I) crystals form in cell combining with peptidoglycan 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 Gram Stain Mechanism

27 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings

28

29 Mycoplasmas (Genus) Lack cell walls Sterols in plasma membrane Archaea Wall-less, or Walls of pseudomurein (lack NAM and D amino acids, peptidoglycan) Atypical Cell Walls

30 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Lysozyme digests disaccharide in peptidoglycan (gram+ cell walls destroyed, gram- damaged, resulting in spheroplast). Spheroplast is a wall-less Gram-positive cell. Penicillin inhibits peptide bridges in peptidoglycan. Protoplast is a wall-less cell. L forms are wall-less cells that swell into irregular shapes (gram+ and -). Protoplasts and spheroplasts are susceptible to osmotic lysis. Damage to Cell Walls

31 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Plasma (cytoplasmic) Membrane Figure 4.14a Learning objectives: Describe the structure, chemistry, and functions of prokaryotic plasma membrane. Define simple diffusion, facilitated diffusion, osmosis, active transport, and group translocation.

32 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings

33 Plasma Membrane – Fluid Mosaic Model Selectively permeable Phospholipid bilayer Peripheral proteins Integral proteins Transmembrane proteins Figure 4.14b

34 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Membrane is as viscous as olive oil. Proteins move to function Phospholipids rotate and move laterally Fluid Mosaic Model Figure 4.14b

35 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Carry enzymes for metabolic reactions: nutrient breakdown, energy production, photosynthesis Selective permeability allows passage of some molecules Enzymes for ATP production Photosynthetic pigments on foldings called chromatophores or thylakoids Damage to the membrane by alcohols, quaternary ammonium (detergents) and polymyxin antibiotics causes leakage of cell contents. Plasma Membrane

36 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings

37 High to low concentration: Movement may be passive (no energy expenditure – diffusion or facilitated diffusion): Simple diffusion: Movement of a solute from an area of high concentration to an area of low concentration. (ions move until equilibrium reached) Facilitative diffusion: Solute combines with a transporter protein in the membrane. Movement Across Membranes

38 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Movement Across Membranes Figure 4.17

39 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Osmosis (always involves water): Movement of water across a selectively permeable membrane from an area of high water concentration to an area of lower water. Osmotic pressure The pressure needed to stop the movement of water across the membrane. Movement Across Membranes Figure 4.18a

40 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 4.18c-e Osmosis

41 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Low to high concentration (against gradient) – cell must expend energy: Active transport of substances requires a transporter protein and ATP. Group translocation of substances requires a transporter protein and PEP. (phospheonolpyruvic acid) Movement Across Membranes

42 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasm is the fluid substance inside the plasma membrane (water, inorganic and organic molecules, DNA, ribosomes, and inclusions) Cytoplasm Figure 4.6a, b

43 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings

44 Nuclear area (nucleoid) – contains single long, continuous, double-stranded DNA called bacterial chromosome. Bacteria can contain plasmids – circular DNA Nuclear Area Figure 4.6a, b Learning objectives: Identify functions of the nuclear area, ribosomes, and inclusions.

45 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Ribosomes = rRNA + proteins Figure 4.6a Sites of protein synthesis (rRNA) – free floating, not tied to endoplasmic reticulum as in eukaryotes.

46 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Ribosomes Figure 4.19 The letter S refers to Svedberg units = relative rate of sedimentation. Because of differences in prokaryotic and eukaryotic ribosomes, the microbe can be killed by antibiotics while eukaryotic host cell is unaffected.

47 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Metachromatic granules (volutin) Polysaccharide granules Lipid inclusions Sulfur granules Carboxysomes Gas vacuoles Magnetosomes Inclusions Phosphate reserves Energy reserves Ribulose 1,5- diphosphate carboxylase for CO 2 fixation Protein covered cylinders Iron oxide (destroys H 2 O 2 ) FUNCTION

48 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Iron-oxide inclusions in some gram-negative bacteria that act like magnets.

49 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Resting cells formed for survival Sporulation: Endospore formation Resistant to desiccation, heat, chemicals Bacillus, Clostridium Germination: Return to vegetative state Endospores Learning objective: Describe the functions of endospores, sporulation, and endospore germination.

50 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Endospores tend to form under conditions of stress.

51 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Eukaryotic Cells Comparing Prokaryotic and Eukaryotic Cells Prokaryote comes from the Greek words for prenucleus. Eukaryote comes from the Greek words for true nucleus.

52 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings

53

54

55 Eukaryotic Flagella and Cilia Euglena (evolutionary building block) Prokaryotic flagella rotate, eukaryotic flagella wave

56 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Flagella and Cilia Flagella are few and long (motility), cilia are numerous and short (motility and move substances along cell surface) Microtubules Tubulin 9 pairs + 2 arrangements Figure 4.23c

57 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cell wall Plants, algae, some fungi contain cellulose Carbohydrates Cellulose, chitin (fungal), glucan & mannan (yeast) Glycocalyx surround animal cells (strength, attachment to other cells) Carbohydrates extending from animal plasma membrane Bonded to proteins and lipids in membrane Cell Wall and Glycocalyx Learning objective: Compare and contrast prokaryotic and eukaryotic cell walls and glycocalyxes.

58 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Phospholipid bilayer in both p. and e. cells Peripheral proteins Integral proteins Transmembrane proteins Sterols Glycocalyx carbohydrates not found in p. cells except Mycoplasma bacteria Plasma Membrane Learning objective: Compare and contrast prokaryotic and eukaryotic plasma membranes.

59 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Selective permeability allows passage of some molecules Simple diffusion Facilitative diffusion Osmosis Active transport Endocytosis Phagocytosis: Pseudopods extend and engulf particles (solids) Pinocytosis: Membrane folds inward bringing in fluid and dissolved substances (liquids) Plasma Membrane

60 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings CytoplasmSubstance inside plasma membrane and outside nucleus Cytosol Fluid portion of cytoplasm CytoskeletonMicrofilaments, intermediate filaments, microtubules Cytoplasmic streamingMovement of cytoplasm throughout cells Eukaryotic Cell Learning objectives: Define organelle. Describe the functions of the nucleus, endoplasmic reticulum, ribosomes, Golgi complex, lysosomes, vacuoles, mitochondria, chloroplasts, peroxisomes, and centrosomes.

61 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Specialized membrane-bound structure in cytoplasm: NucleusContains chromosomes (DNA) ERTransport network, ribosomes Golgi complexMembrane formation and protein secretion LysosomeDigestive enzymes VacuoleBrings food into cells and provides support MitochondrionCellular respiration (ATP) ChloroplastPhotosynthesis (70S ribosomes) PeroxisomeOxidation of fatty acids; destroys H 2 O 2 Organelles

62 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Not membrane-bound: RibosomeProtein synthesis (translation) CentrosomeConsists of protein fibers and centrioles CentrioleMitotic spindle formation Eukaryotic Cell

63 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Eukaryotic Nucleus Figure 4.24

64 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Endoplasmic Reticulum Figure 4.25 Rough ER contains ribosomes – site of protein translation Smooth ER performs various functions: Synthesizes phospholipids, fats, steroids In liver: glucose release and detoxify toxins Creates vesicles

65 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings 80S Membrane-boundAttached to ER FreeIn cytoplasm 70S In chloroplasts and mitochondria Ribosomes

66 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Golgi Complex Figure 4.26 Golgi complex modifies, sorts, and packages proteins received from the ER; discharges proteins via exocytosis; replaces portions of the plasma membrane; and forms lysosomes (digestive enzymes).

67 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Lysosomes (digestive enzymes) Figure 4.22b

68 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Vacuoles (storage of toxins, food, water) Figure 4.22b

69 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Mitochondrion (furnace of the cell) Figure 4.27 Site of the Krebs Cycle, which produces the energy currency of the cell - ATP

70 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Chloroplast Figure 4.28 Structure similar to mitochondria – the reverse side of respiration: C 6 H 12 O 6 + O 2 = H 2 O + CO 2 + ATP Photosynthesis: H 2 O + CO 2 + sun = C 6 H 12 O 6 + O 2

71 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Endosymbiotic Theory Figure 10.2 Learning objective: Discuss evidence that supports the endosymbiotic theory of eukaryotic evolution. Mitochondria and chloroplasts resemble bacteria in size and shape as do their ribosomes These organelles contain circular DNA like prokaryotes and can reproduce apart from their host cell


Download ppt "Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation prepared by Christine L. Case Microbiology."

Similar presentations


Ads by Google