140 MBio Lecture
Phase-Contrast Microscopy Dark-Field Microscopy
Fluorescence microscopy
The electron microscope: 1- Transmission Electron Microscopy 2- Scanning Electron Microscopy
Differential interference Contrast microscopy Atomic force microscopy Imaging Cells in Three Dimensions
Confocal Scanning Laser Microscopy
Classification of living organisms The modern classification of five Kingdoms system of living organisms, according to Whittaker (1969), classify the living organisms to five kingdoms: Living Organisms Monera Protista Fungi PlantaeAnimalia
Microorganisms Prokaryotic cells Eukaryotic cells Cyanobacteria Bacteria Archaea Fungi (Molds and Yeast) Algae Protozoa ( Parasitic worms) Helminths
Major Differences between prokaryotic and eukaryotic micro-organisms ProkaryotesEukaryotes 1- Lack membrane bound nucleiod region 1- Membrane bound nucleus containing DNA 2- DNA-one circular molecule one chromosome 2- DNA-linear molecules arranged to form several chromosomes 3- Haploid-One copy of a gene2- Diploid-Two copies of a gene 4- Plasma membrane does not contain sterols 4- Plasma membrane contains sterols 5- Reproduction—simple binary fission 5- Reproduction—meiosis and mitosis
ProkaryotesEukaryotes 6- lack membrane bound organelles6- Presence of membrane bound organelles such as chloroplasts and mitochondria 7- Cell walls almost contain complex polysaccharide Peptidoglycan 7- Cell wall is chemically simple when present Major Differences between prokaryotic and eukaryotic micro-organisms
Eukaryotic cellsProkaryotic cells Organism Algae, Fungi, Protozoa, plant, AnimalBacteria, Cyanobacteria Diameter greater than 5 µm 1-4 µ m or less Size Multi-fiber (9+2) of microtubuleSimple fiber Members of the movement YesNo Pseudopodia NOYes Cell walls (Peptidoglycan) YesNo Cytoplasmic membrane Sterols NoYes Cytoplasmic membrane Respiratory enzymes NoYes Cytoplasmic membrane Optical pigments YesNo Cytoplasmic motion YesNo Pinocytosis NoYes Mesosomes Located in endoplasmic reticulum, type of 80s Distributed in cytoplasm, type of 70s Ribosomes YesNo Mitochondrion YesNo Chloroplast YesNo Golgi complex YesNo Endoplasmic reticulum YesNo Vacuole (enclosed membranes) NoMay present Gas vacuole