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 Functional Anatomy of Prokaryotic and Eukaryotic Cells
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Prokaryotic Cells Prokaryote : Greek word for “pre-nucleus”.
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Size: µm µm Shape: Morphological characteristics Basic shapes Spherical(cocci) Rod- shaped (bacilli) Spiral Spirochete Vibrio (comma-shaped)
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Unusual shapes Star-shaped Square or rectangular Most bacteria are monomorphic A few are pleomorphic
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings. Arrangements Pairs: diplococci, diplobacilli Clusters: staphylococci Chains: streptococci, streptobacilli
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Structure of prokaryotic cells Outer cell layers Glycocalyx Cell wall Plasma membrane Cytoplasm Nuclear material Flagella Fimbreae Ribosomes
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Glycocalyx Outside cell wall Usually sticky Either neatly organized called a capsule Or unorganized & loose called a slime layer Extracellular polysaccharide allows cell to attach Protect bacteria from phagocytosis
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cell Wall Prevents osmotic lysis Made of peptidoglycan (in bacteria)
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Peptidoglycan Polymer of disaccharide N-acetylglucosamine (NAG) & N-acetylmuramic acid (NAM) Linked by polypeptides
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Gram positive Vs. Gram negative cell walls Thick peptidoglycan Teichoic acids Lack outer membrane No periplasmic space Thin peptidoglycan No teichoic acids Outer membrane Periplasmic space
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Gram-Positive cell walls Teichoic acids: Lipoteichoic acid links to plasma membrane Wall teichoic acid links to peptidoglycan May regulate movement of cations Polysaccharides provide antigenic variation
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Gram-Negative Outer Membrane Lipopolysaccharides, lipoproteins, phospholipids. Lipopolysaccharide consists of two parts Lipid A is an endotoxin. O polysaccharide antigen, e.g., E. coli O157:H7. Protection from phagocytes, complement, antibiotics
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Plasma Membrane Phospholipid bilayer Peripheral proteins Integral proteins Transmembrane proteins
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Plasma Membrane 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.
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings 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. Osmosis Active transport
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Osmosis and osmotic pressure
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Flagella Outside cell wall Made of chains of flagellin Attached to a protein hook Anchored to the wall and membrane by the basal body
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Motile Cells Move toward or away from stimuli (taxis) Flagella proteins are H antigens (e.g., E. coli O157:H7)
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Axial Filaments Endoflagella In spirochetes Anchored at one end of a cell Rotation causes cell to move
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Fimbriae allow attachment Pili are used to transfer DNA from one cell to another Fimbriae and Pili
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasm Cytoplasm is the substance inside the plasma membrane
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Ribosomes Prokaryotic ribosome consists of two subunits: 1.Small 30S subunit 2.Large 50 S subunit. Complete 70S ribosome
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nuclear Area Nuclear area (nucleoid) An area containing the genetic information. Unlike the eukaryotic cells, it is not surrounded by a membrane.
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Eukaryotic Cells Eukaryote : Greek word for “true nucleus”.
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cell Wall Cell wall Plants, algae, fungi. Animal cells do not have a cell wall. Plant and algae cells : mainly made of cellulose Fungal cells: mainly made of chitin.
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Flagella and Cilia Structure of flagellum Microtubules Tubulin 9 pairs + 2 arrangements
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Plasma Membrane Phospholipid bilayer Peripheral proteins Integral proteins Transmembrane proteins Sterols Glycocalyx Carbohydrates extending from animal plasma membrane Bonded to proteins and lipids in membrane
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Plasma Membrane: Functions Selective permeability allows passage of some molecules Simple diffusion Facilitative diffusion Osmosis Active transport Endocytosis Phagocytosis: Pseudopods extend and engulf particles Pinocytosis: Membrane folds inward bringing in fluid and dissolved substances
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Eukaryotic Cell: Cytoplasm CytoplasmInside to plasma membrane membrane CytosolFluid portion of cytoplasm CytoskeletonMicrofilaments, intermediate filaments, microtubules Cytoplasmic streamingMovement of cytoplasm throughout cell Organelles Membrane - bound structures within the cytoplasm
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Organelles Membrane-bound: NucleusContains chromosomes ERTransport network Golgi complexMembrane formation and secretion LysosomeDigestive enzymes VacuoleBrings food into cells and provides support MitochondrionCellular respiration ChloroplastPhotosynthesis PeroxisomeOxidation of fatty acids; destroys H 2 O 2
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nucleus Figure 4.24
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Endoplasmic Reticulum (ER)
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Ribosomes 80S Membrane-boundAttached to ER FreeIn cytoplasm 70S In chloroplasts and mitochondria
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Golgi Complex
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Lysosomes
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Vacuoles
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Mitochondrion
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Chloroplast
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings 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