6. Flashcards
(10 cards)
1
Q
scanning electron microscopy (SEM)
A
- specimen is coated with a thing film of heavy metal (ex gold)
- an electron beam scans the object
- scattered electrons are collected by a detector, and an image is produces
- allows an accurate 3D image of specimens surface
2
Q
cell mophology
A
cell shape
3
Q
coccus shape
A
roughly spherical
ex. streptococcus pyogenes
4
Q
bacillus shape
A
rod shaped
ex. E. coli
5
Q
spirillum
A
- spiral shaped
ex. spirillum volutans
6
Q
cells with unusual shapes
A
- spirochete
- treponema pallidum
- budding and appendaged bacteria
- caulobacter crescentus
- filamentous bacteria
- streptomyces griseus
7
Q
morphology typically does not predict…
A
physiology, ecology, phylogeny, etc. or a prokaryotic cell
8
Q
may be selective forces involved in setting the morphology
A
- optimization for nutrient uptake (small cells and those with high surface to volume ratio)
- swimming motility in viscous environments or near surfaces (helical or spiral shaped cells)
- gliding motility (filamentous bacteria)
9
Q
prokaryotes size
A
0.2um to >700um in diameter
despite the overlap in size with eukaryotes it can be said the prokaryotes are very small compared with eukaryote
10
Q
eukaryotes size
A
10 to >200um in diameter
