better exam 1 Flashcards
Woese 3 domain scheme is based on
sequence similarities of small subunit rRNAs
evolutionary relatedness
phylogeny
whittaker system
plantae, animalia, fungi, Protista, prokaryote based on morphological differences
prokaryote shapes
Most common - coccus and rod
other - vibrio, spirllum, spirochete
spherical bacteria types
staypylococcus -irregular bunches
streptococcus - chains
diplococcus - pairs
sarcina - packets of eight or more
tetracoccus - four cells & more in a sheet
cylindrical bacteria
singular bacillus
pairs
chains
palisade
can have spores
coccobacillus
elongated coccus or short oval-shaped rod
spiral bacteria
spirochetes - flexible, axial filaments (periplasmic flagella)
spirilla - rigid, polar flagella
vibrios - bent rods, comma shaped
16S rRNA is a component of
the ribosome
G+ bacterial cells
thick PG layer, larger than eukaryotes, rare proteins/ribosomes, sensitive to lysozymes/penicillin, more penetrable
G- bacterial cells
thin PG layer, outer membrane (out - LPS, I-phospholipids), less penetrable
protoplast and spheroplasts
proto - formed after g+ loses PG, all cell wall material removed
sphero - formed after g- loses PG, some cell wall left
L-form bacteria
no cell walls (mycoplasma - not affected by penicillin/lysozymes)
archeaeoblasts have cell walls made of
other material then PG
glycan chains of pG are cross-linked by
peptides
porins
proteins that form non-specific channels across OM, allow passage of small molecules
endotoxin (lipid A)
part of LPS in OM, causes toxivity in BS, heat stable, cause fever, septic shock, inflammation
transmission e- microscope
electrons pass through thin metal treated specimen and 2D image formed
Mag - 1,000,000 X. Res - 0.2nm
scanning e- microscope
electrons bound off metal-treated specimen’s surface, are collected, and create 3D image
mag - 100,000-300,000 X, resolution of 2 nm
light microscope
uses visible light of 400-800 nm wavelength
upper limit is 1500-2000 X magnification; res of 200 nm
simple - 1 lens
compound - 2 lenses
when a bacterial cell divides on more than two planes repeatedly, it will rise to what arrangement
sarcina, staphylococci, and tetrad
short vs long wavelength em spectrum
short - x-rays, gamma, electron
long - radio, microwave, infrared
contrast
exaggerate btw light and dark parts of image
stains - basic and acidic
basic - cationic, will color -charge cells via + charged chromophore
acidic - anionic chromophore, stain background
resolution
ability of lenses to distinguish btw two pts at specified distance apart
magnification
enlarging an image
wet mounts detect motility to be distinguished from
mass flow of H2O in cells & Brownian motion (passive)
atomic force microscope
high resolving power, sharp scanning probe, not prep
streptococcus pyogenes (domain, shape, gram, blood agar, can cause, treat)
bacteria
coccus; non-motile; pairs/chains
gram +
beta-hemolytic
scarlet/rheumatic/puerperal fever, necrotizing fascitis, impetigo, toxic shock, strep throat
treat with antibiotics (penicillin)
subatomic particle size
10^-15 m
atom size
0.1-0.5 nm
molecule size
0.1-0.275nm
macro size
100-10000 ang
viruses size
20-400nm
pro size
0.1-5 um
protist size
protozoa - 10-1000 um
algae - 10-500 um
fungi size
yeast - 5-30 um
mold cell - 5-100 um
eukary size
5-100 um
vibrio cholerae (domain, shape, gram, can cause, treat)
bacteria
vibrio
g-
EC toxin = diarrhea, cholera, vomiting, cramps, dehydration, shock electrolyte imbalance in SI
treat with oral rehydration or antibiotic therapy to shorten duration
van Leeywenhoek
made own glass lenses & simple microscopes (300X)
observed bacteria, protozoans, and yeast
Jenner
Vaccine for smallpox through inoculation
Semmelweis
wash hands to prevent childbed fever with calcium hypochlorite
Snow
study dosages for surg anesthetics and public water pump causing cholera. Father epidemiology
Koch
certain bacteria cause certain diseases
- anthrax, cholera, tb
Koch’s postulates
stained bacteria to be observed with bright-field microscopy
Pasteur
microbial control technique for preserving food/liquid
vaccine for rabies
swan-neck flasks
Lister
first work on antiseptic surgery - use phenol to sterilize everything
koch’s postulates
The microorganism must be present in people who have the disease, but not in people who are healthy.
The microorganism must be isolated from a person who has the disease.
The microorganism must cause the disease when introduced to a healthy person
The microorganism must be re-isolated from the person who became sick after being introduced to it, and it must be the same microorganism that was originally isolated.
