Ch10 Classifying Microbes Flashcards
define taxonomy
put organisms into categories (Taxa), shows degrees in similarities/relatedness
define systematics/ phylogeny
study of evolutionary history of organisms
the hierarchy of taxa reflects …
phylogeny (evolutionary relationships)
plants, animals, and fungi are in what domain
eukarya
prokaryotes w peptidoglycan in cells walls, pathogenic, non-pathogenic, or phototrophic, are in which domain
bacteria
prokaryotes w/o peptidoglycan in cell walls in what domain
archaea
what is the endosymbiosis theory, what does it explain
says that eukaryotic cells evolved from prokaryotic cells living in one another (endosymbionts)
explains origin of chloroplasts and mitochonria
what evidence is there to support the endosymbiosis theory
list
similarities between prokaryotic cells and eukaryotic organelles (mitochondira and chloroplasts)
both have…
-circular DNA
-1st amino acid in protein synthesis= formylmethionine
-70s ribosomes
-grow by binary fission
-have double membranes
the theory of endosymbiosis was developed by
Lynn Margulis
how carl woese based his 3 domain classification system on
RNA sequence of ribosomes
archaea RNA is more similar to prokaryotes or eukaryotes
eukaryotes
list taxonomic hierarchy from largest to smallest
Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
1st step in identifying bacteria, important for determining antibiotic to use
differential staining
how biochemical tests are used to identify microbes
test enzymatic activities (what it can consume via fermentation tests, what can i produce)
examples of biochemical tests
agulation tests, enterotubes
what is phage typing
test for determining which phages a bacterium is suseptible to (usu only affects members of a certain species)
what are agglutination tests
samples of unknown bacterium placed in drop of saline on several slides, antiserum added, bacteria agglutinate (clump) when mixed w antibodies produced in response to bacterium
what western blotting is used for
identify antibodies in patient’s serum
steps in western blotting
- proteins from a known bacterium or virus separated by electrophoresis
- proteins(antigens) transferred by blotting
- patient’s serum washed over filter, if serum has antibodies for the known microbe combines w antigens
- anti-human serum linked to an enzyme rinsed over filter
- after adition of enzyme, colored band visible
what is a cladogram
map that shows evolutionary relationships among organisms
2 RNA sequences are aligned, % of similarity is calculated, branched drawn proportional to similarity (shorter= more similiar)
what is a dichotomous key
identification based on sucessive questions, each w two possible answers
