1. Cytoplasmic (Cell) Membrane Located just inside the peptidoglycan layer. Phospholipid bilayer similar to eukaryotic membranes, but does not contain sterols (except Mycoplasma species). Functions:
like a stiff “canvas sack” around the bacterial cell. maintains cell structure. is a permeability barrier to large molecules (like lysozyme) and hydrophobic molecules; also
Structure Chemical Composition Function Essential Components Cell Wall Peptidoglycan Outer membrane of Gram- negative bacteria Surface fibers of
Name Reason Alternative Microscopic Approach Mycobacteria (Ex. M. tuberculosis) Too much lipid in cell wall so dye cannot penetrate Acid-fast stain Treponema pallidum Too thin
It is difficult to classify all bacteria into clear-cut categories. Various classification methods are used, depending in part, on the purpose. Nomenclature Bacteria are
Property Prokaryotic Bacterial Cells Eukaryotic Human Cells DNA within a nuclear membrane No Yes Number of chromosomes 1 More than 1 Mechanism of Replication
Learning Objectives: You should be able to: describe the major differences between eukaryotic and prokaryotic cells and explain why it is important to know the
The study and diagnosis of infectious diseases is approached from an organ system perspective. Upper and Lower Respiratory Tracts Gastrointestinal Tract Urinary Tract Genital Tract
A. Observations of “acquired immunity” to diseases and primitive vaccination practices contributed to our understanding of the immune response to infectious agents and the design
Relative sizes of microorganisms: Protozoa > Red Blood cell > Yeast > Bacteria > Mycoplasma > Viruses Fungi 1. David Gruby (1841-1845) identified yeast infections
