Classifying Microbes Flashcards
Taxonomy
A field of science that deals with 3 separate but related areas
Classification
The process of arranging organisms into groups (or taxa)
Nomenclature
The assignment of names to various taxa
Identification
The process of determining whether organism belong within one of the established taxa, or should be assigned to a new taxa
Binomial system
Each organism is given two names
First name = Genus
Second name = Specific epithet
Together = Species
Classification of bacteria steps
Nomenclature Shape Cell wall composition Morphology Mortile or non Pathogenic or non Sensitivity or resistance to antibiotics or chemicals Lactose or no lactose fermenting Oxygen requirements
Shapes of bacteria
Spherical (cocci)
Rod (Bacilli)
Spiral (Spirilla)
Cell wall compositions and how this is identified
Gram positive Gram negative blue/purple dye = gram positive Red/pink = gram negative For mycobacterium cell wall has waxes - use acid-fast strain (appears as red)
Morphology
Rapid division (binary fission) produces a mound of bacteria (colony) that can be seen by the naked eye Features include: Size Colour Overal Shape Elevation Margin
Motile vs non
Possess flagella and are able to move vs no flagella
Types of oxygen requirements
Obligate aerobes Obligate anaerobes Microaerophiles Aerotolerant anaerobes Facultative anaerobes
Obligate aerobes
Bacteria that have an absolute requirement for an atmosphere with around 20% oxygen (room air)
Obligate anaerobes
Bacteria that can only grow in an anaerobic environment(no oxygen)
Microaerophiles
Bacteria that also have an absolute requirement for an oxygen containing atmosphere but require a lot less (around 5%)
Aerotolerant anaerobes
Bacteria that can grow in an atmosphere with oxygen, but they grow better in atmospheres with no oxygen
