EXAM 2 P3 Flashcards
coccus or cocci
grow in particular formats
diplococci
pairs of cocci
this form seen growing in the spinal fluid indicates the worst form of meningitis
streptococci
chains of cocci
gives you strep throat and ear infections
divides in 1 plane down the middle of the cell
tetrads
groups of 4 cocci, dividing in 2 planes
sarcinae
cubes of cells, shifting 90 degrees in 3 planes
staphylococci or micrococci
irregular bunches or clumps, dividing in many planes
rods
bacillus or bacilli
vibrio
rod shaped but curved
spirillum
1 to several helical turns
spirochete
very tight helix with 10-100 helical turns
filamentous bacteria
long, straight chains
appendages
extensions called hypha (just protruding) or stalks (used for attachment with sticky ends)
what affects cell shape and size
the surface area to volume ratio and the number of cells produced per unit of nutrients available
cytoplasmic membrane
made of lipids containing a glycerol (head) with phosphate attached
head (glycerol)
positively charged
hydrophilic (likes water)
phosphate
negatively charged
fatty acid side chains
neutral charge
hydrophobic (doesn’t like water)
amphipathic
having both hydrophilic and hydrophobic regions
characteristic of lipids
membrane fluidity
they take shape defined by the cell wall
50% lipids, 50% proteins
integral transmembrane proteins
reach both sides of the cell and form channels through the membrane
peripheral proteins
on the surface of the membrane, NOT buried within
lipoproteins
covalently linked to a lipid, keeping it associated with the membrane
R groups
these are fatty acids and phytonyls
bound by ester bonds for bacteria and eukarya
bound by ether bonds for archaea
passive transport
moves down the concentration gradient (high to low)
no energy required
active transport
moves up the concentration gradient (low to high)
cellular energy required
simple diffusion
passive mechanism
small nonpolar and uncharged polar molecules can cross the membrane
includes glycerol, H2O, CO2
aquaporins
water transport channels that make movement faster
facilitated diffusion
passive mechanism
produces cells that increase diffusion rate across the membrane
requires channel and carrier proteins that move back and forth.
simple transport
active mechanism
depends on PMF
uniporter
facilitated with diffusion
lets one molecule cross down the gradient
antiporter
moves in the opposite direction
drives molecules out as protons move in
most commonly sodium ion
symporter
move in the same direction
as protons move in, ions move in as well
group translocation
active mechanism
phosphotransferase systems (PTS) moves sugars from the environment inside the cell. high energy phosphate is removed and becomes pyruvate. proteins take phosphate and transport it to the transported molecule, glucose.
THIS IS ONE OF THE FIRST STEPS OF GLYCOLYSIS
PTS conserves 1 ATP by transporting and phosphorylating sugar in one step
energy source is PEP, phosphoenolpyruvate
ABC system
active mechanism
ATP binding cassette
3 protein system
periplasmic binding protein is outside the membrane and tightly binds the molecule to be transported
channel protein is a transmembrane protein
cytoplasmic ATP hydrolyzing protein hydrolyzes ATP and force the channel to move the substance from out to in.
