MICR 3050- Majors Final Exam Unit 1

Koch

Established the caused and effect of germs and disease
(Matched bacteria with its disease)
Ex: Bacillus anthracis and Anthrax

Cohn

Discovered bacterial endospores
Classified bacteria based on shape

Lister

Developed system of surgery designed to prevent microbes from entering wounds

Leeuwenhoek

First to observe and accurately describe bacteria

Jenner

Discovered and used the smallpox vaccine to protect individuals

Pasteur

Disproved Spontaneous Generation
Microorganisms carry out fermentation
Pasteurization
Rabies, anthrax, and chicken cholera vaccines

Size Range for Eukaryotes

0.8 um to millions of um

Size Range for Bacteria/Archaea

0.2 um to 750 um

Size Range for Viruses

0.01 um to 2.3 um

Universal Phylogenetic Tree is a 3 domain system based on...

The comparison of the DNA encoding small subbunit ribosomal RNA

Microbial Species

Collection of strains that share many stable properties and differ significantly from other groups of strains

Microbial Strain

Consists of the descendents of a single, pure microbial culture

3 methods to inrease the resolution under a microscope

1. Shorter wavelength (blue light)
2. Increase the numerical aperature (closer to the slide)
3. Increase the refractive index (immersion lens)

Gram Stain

Differential Stain
Divides bacteria into 2 groups based on cell wall characteristics

Crystal Violet

Colorizes Gram+ and Gram- cells purple
Primary Stain

Iodine

Mordant
Creates a Crystal Violet-Iodine complex that helps the stain bind to the cell wall

Ethanol

Decolorizer
Shrinks the spaces between CVI complexes in Gram+ cells
Removes the crystal violet from the Gram- cells

Safranin

Secondary Stain
Repelled by Gram+ cells
Taken up by Gram- cells

Acid Fast Stain

Differential stain that distinguishes between bacteria with mycolic acid in the cell walls

Endospore Stain

Differential stain that distinguishes between between vegetative cells and endospores

What bond do lysozymes break?

Beta 1,4 Glycosidic Bonds

What bond does penicillin break?

Peptide Bonds

3 Exterior characteristics of bacteria that can contribute to pathogenicity

Capsules
Slime Layers
Fimbriae/Pili/Flagella

4 things that endospores are resistant to?

Heat
Radiation
Chemicals
Dessication

General Purpose Media

Supports the growth of microbes

Selective Media

Favors the growth of some microbes and inhibits the growth of others

Differential Media

Distinguishes between different groups of microbes based on their biological characteristics

Pure Culture

population of cells arising from a single cell

2 Functions of Peptidoglycan

Helps provide shape to the cell
Contributes to pathogenicity

2 Functions of LPS

Stimulates antibody and immune processes via O Antigen
Endotoxin capabilities via lipid A