chap 2, Cell exterior Flashcards
cell exterior of prokaryotic cells
all eukaryotic cells have
cytoplasm, ribosomes, plasma membranes, nuclei containing DNA
cell envelopes
surrounds cytoplasm of prokaryotes
made of cell membrane, cell wall, appendages attach here
monomorphic
single shape- most bacteria
pleomorphic
many shapes/forms
spiral shapes
vibrio (one bend), spirillum (twisty, usually have flagella, ridgid), spirochete (corkscrew)
Nucleoid
prokaryote location of chromosome
pairs prefix (2)
dip
cluster
Staphylo
chains
Strepto
tetrads
four, cube like
sarcine
groups of 8
bacillus
rod
coccus
spherical
morphology effects
nutrient intake, motility (swimming and gliding)
resolution
ability of a lens to distinguish between two points
refractive index
light bending ability of medium/ microbe
light microscopy
white light (0.2 microns), stains,
TEM
electron microscopy, sections, 0.01 nm resolution (high), shows internal structures
SEM
electron microscopy, 10nm resolution, shows surfaces
scanning probe microscopy
can see atoms, surface? yea idk
cryo-EM
sample is flash frozen and prepared
cell membrane is a - and consist of
selective permeable barrier, consist of: phospholipid bilayer, proteins, some have sterol
Archaeal mono layer
more stable and resistant than bilayers
where is ion gradient formed
cell membrane
ion gradient produces
ATP, proton-motive force
cell wall fuction
shapes cell, anchors appendages, protects membrane and cell interior, prevents osmotic lysis
cell wall major component (bacteria)
peptidoglycan, murein
4 types of bacteria (based on cell wall/staining)
gram positive, gram negative, acid fast, mycoplasmas
gram positive
thick cell wall, purple, teichoic acids, lipoteichoic acids
gram negative
thin cell wall, has outer membrane, red, LPS, harmful chem resistant, periplasm
Peptidoglycan held together by
NAG and NAM
teichoic acids
(gram +) links to peptidoglycan (wall), regulate movement of cations, has antigenic variations, provides ridgity, adheres to stuff
lipoteichoic acids
links wall to membrane (attached to phosolipid)
gram negative cell wall is made of
lipid a, core polysaccharide, o antigen repeating subunits
lipid A is
an end toxin, can only release if cell is dead
outer membrane premeability
less permeable than inner
porin
(-) allows small hydrophillc molecules to enter cell
transport systems
(-)special proteins that allows larger hydrophilic things in cell
periplasm
(gram -) space between inner and outer membrane, **contains murein, **proteins that help with nutrition, has enzymes, solution of cell wall precursors
acid fast
mycolic acids (wax, branched hydrocarbon), slow growers, impermeable,
gram positive intake nutrients with
transport proteins
gram negative nutrient intake via
trans. proteins, porins
mycoplasmas
no cell wall/peptidoglycan, contains sterols
s layer
archaea, protein layer surrounding cell, selectively permeable, anchors enzymes, shapes, glycoproteins
archaea cell wall
most have none, will have s layer
capsule
well attached, uniform, prevents phagocytosis, retains water and nutrients, chemical protectant, involved in attachment
slime layer
looser, prevents phagocytosis, retains water and nutrients, chemical protectant, involved in attachment
exoploysaccaride (EPS)
released polysaccharide (sugar), sticky outer layer, gelatinous,
biofilm
microbe community, made of microbes with slime/capsules
acid fast nutrient intake via
small protein channels, slow
murein is composed of
N-acetylmuramic acid (NAM), N-acetyl-d-glucosamine (NAG), cross linked peptides, D amino acids
LPS
provide structural integrity and a permeability barrier
mycolic acids
acid fast, branched
hydrocarbons, 60-90 carbons long)
Psuedomuerin
Archaea, different linkage of sugar backbone and
L amino acid
capsule and slime layer is made of
made of polysaccharides/peptides