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Movement into and out of Cells, o2 - channel, na+ - Coggle Diagram
Movement into and out of Cells
passive trsansport - no energy moved - high to lo
Osmosis
type of diffusion
solvent moves fm low to high solute conc through selectively permeable membrane
till equalw
water potential
tendency of water to leave in place in favour of another/ measure of degree to which osmosis occurs
high wat.pot - dilute solution
low w.pot - conc solution (more solute)
factors affecting water potential
conc of solute (solute potential)
solute potential - contribution of concentration of solute to the w.pot (negative value)
w.pot = solute potential+pressure potential
pressure applied to solution (pressure potential)
apply pressure - water moves to other side, solution gets more concentrated
blue arrow - water moving in
red arrow - pressure applied on cell wall
-2 because solute is present
pressure and solute
pressure fm inside - positive - w.pot becomes negative
negative - outside to inside
measured in megapascals MPa (100 kPa)
for pure water at sea leven and room temperature - w.pot = 0
add solute - value becomes negative
greek letter - psi
tonicity
hypertonic - more solute outside
cell
than inside
exosmosis - water moves out of cell into beaker
cell flaccid
if this continues for a long time - cell plasmolysed
contents of cel shrinks - cell permanently damaged
if put into distilled quickly before - cell saved
plasmolysis
incipient plasmolysis
2 more items...
evident plasmolysis
2 more items...
final plasmolysis
2 more items...
in animal cell - (rbc)
3 more items...
isotonic - inside and outside is same
water entering and leaving is same - net =0
plant cell - flaccid
hypotonic - beaker dilute, inside concentrated
endosmosis - water enters cell
cell turgid - puffed out
Simple Diffusion
movement of molecules or ions from a region of it's high to low conc, till equal distribution
because of random motion - its kinetic energy
can happen with or without semi permeable membrane
factors affecting
temperature - high temp, high kinetic, so faster
surface area - smaller - more surface area:volume ratio, so more diffusion
larger molecule - surface:vol ration decreases - diffusion fater when high ratio
concentratoin gradient
high - fast diffusion
steep gradient - faster diffusion
size and nature of particles
smaller - faster diffusion
higher in gas - liquid - solid
polar and non polar
non polar - high rate
uncharged polar
h2o, glycerol, ethanol can pass (they're small), but glucose can't so facilitated diffusion
coz they're too big - glucose, amino acids, nucleosides
ions - can't pass coz of their charge
facilitated diffusion
proteins embedded in cell help with diffusion
2 TYPES OF PROTEINS - channel and carrier
type of diffusion
channel
fixed shape
have water filled pores, opening in center, can be gated - free movement, but gated - restrictions
so hydrophyllic can pass
specific - exclusively transport ions
have a signalling molecules to alert to open - these are for gated proteins
usually Na+ and K+
aka neurotransmitter
carrier
not fixed shape
change shape to allow molecules through
transport molecules - complementary to some
specific
glucose
large, and soluble - so can't pass
carrier protein has a glucose binding site - changes shape to push glucose in - then returns to normal
not active transport - no energy is transferred
Active transport
movement of molecules against conc gradient using energy fm atp
to inside or outside cell
called protein pumps (carrier proteins)
pump fm low to high energy
site for atp - receptor site
aptase enzyme - hydrolysis of atp to adp and inorganic phosphate
for energy, but also 2. for carrier protein to change shape
when you see atp - it means active transport
sodium potassium pump
maintain equilibrium of na and k inside and outside cell
interaction of cardiac muscles, in kidney - reabsorption, nerve signals
2 types of ions moving
for every 3 na ions, which move out, 2 k ions enter - the carrier protein flips
lots na inside, lots k outside, so moves against gradient
types of active transport
endocytosis
substances entering cell
phagocytosis (for bacteria - digests)
phagosome - wbcs
for eating
wbc can change shape
pathogen comes in, recognised
membrane enfolds
bacteria in newly-formed vesicle (phagosome)
combines with lysosome (digestive
1 more item...
pinocytosis
movement of solvent/solution/fluid/liquid
drinking process
liquid
process
bulk solution
membranne enfolds
deeper folding, then vesicle detached fm membrane
1 more item...
bulk movement of solid particles in bulk
exocytosis
moving materials out of cell
digestive enzymes produced by pancreas moved out
vesicle with substances
fuses with membrane
releases substances outside cell
waste materials - lysosomes
plant cells - synthesis of cellulose
glucose transported - through cell membrane, so exocytosis
both for bulk transport
too large for carrier protein, so bulk molecule moves through vesicles
bunch of molecules, or a big molecule - eg starch
o2 - channel, na+
