{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

MIC201 Lecture Notes

MIC201 Lecture Notes - Microbiology 201 Dr Jay F Sperry...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Microbiology 201 Dr. Jay F. Sperry Room 117 Morrill Hall I. Objectives of the Course {Mine versus Yours}? A. Breadth of Microbiology B. where does it fit into your world? C. Everyday interaction with microbes. II. Textbook: Fundamentals of Microbiology , 5th ed. 1997 Alcamo III. Grading [handout] - - very slight scale MICROBIOLOGY - "The study of small organisms" - bacteria, yeasts, molds, algae, protozoa and viruses: plus immunity {microbe interactions with macrobe} SURVEY OF MICROBES PROCARYOTES EUCARYOTES bacteria & cyanobacteria all else a) nuclear membrane b) nucleolis c) organelles d) mitosis e) flagella are complex Bacteria - contain a single chromosome, divide by fission, can grow & exist in a wide variety of environments. Rickettsia, Chlamydia & Mycoplasma - very small unusal Viruses - Are they alive? DNA or RNA + protein replicate only in a host cell = obligate intracellular parasite cause numerous diseases {smaller than bacteria} Protista (Protozoa) - Eucaryotes (animals) - mitosis; blood and tissue diseases Fungi - Molds & Yeasts - no chlorophyll; fermentation and food, industrial products, antibiotics; decomposers of dead organic matter Algae - chlorophyll containers (chloroplasts) - diatoms and dinoflagellates TAXONOMY Whittaker (1969) Five Kingdoms 2
Background image of page 2
I. Procaryotae - bacteria, bluegreen algae & archaebacteria II. Fungi - Yeasts & Molds III. Protista - protozoa IV. Plantae V. Animalia Woese (1988) Three Domains I. Eubacteria II. Archea (more related to the Eukarya than to the Eubacteria) III. Eukarya (Kingdoms: Fungi, Protista, Plantae & Animalia) Genus species (strain) Bergeys Manual of Determinative Bacteriology (1923) first publication Division II Bacteria - 19 parts Identification - a) size; b) shape; c) motion or lack of; d) pathogenic for humans or animals; e) growth requirements; f) staining reactions; g) antigenic nature; h) DNA base ratio or DNA-DNA homology. Size - μ m = 1 millionth of a meter = 1 thousanth of a mm Protozoa 100 μ m (0.1mm) Fungi 10 X 40 μ m Bacteria 0.3 - 2 μ m X 0.5 - 20 μ m Viruses 20 - 250 nm [0.02-0.25 μ m] Microscopes Light Microscope - used for discerning: size, shape, staining characteristics and microscopic arrangement Limit of Resolution = 0.2 - 0.25 μ m with an oil immersion objective Darkfield Microscopy - Inverts the image; good for thin microbes ( Treponema pallidum ) Electron Microscope - Transmission Electron Microscope (TEM) & Scanning Electron Microscope (SEM) = Total Magnification about 20 X 10 6 X (observe object 1 nm) Magnets act as lenses for focussing SEM - gives a three-dimensional image 10 12 bacteria/g dry weight (2 X 10 11 bacteria/g wet weight) Food Microbiology Bacteria and molds eat the same foods that we do! 3
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Important constituents: organic matter , water content and pH A. Spoilage [a waste of money and a source of illness] 1. spices - a cover up (also sauces) for unpleasant appearance, odor or taste 2. food intoxications and food infections may not be obvious 3. contaminants: airborne, animal intestines, soil, contaminated water, insects, humans involved in food processing B. Conditions of the food : (1) water content, minimum of 18-20%; (2) pH down to 5 for
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}