Transport across membraness Flashcards
Simple diffusion
is the movement of molecules from a region of higher concentration to one of lower concentration.
Specifically, osmosis
is diffusion of water across a selectively permeable membrane
If one solution contains 20% NaCl and another contains 30% NaCl. The 30% solution is
hypertonic, compared to the 20% solution.
Frog eggs usually do not have aquaporins. When the eggs are put in distilled water, these eggs will
remain unchanged in shape.
water cannot enter the cell without aquaporins because the cell membrane is
hydrophobic
Scientists are now able to put aquaporins on frog eggs for experimental purposes. When these manipulated eggs are put in distilled water, these eggs will
swell and possibly burst.
Hypotonic solution for animals
BURST
There is more SOLVENT then solute… Solvent moves to solute
HypOTONIC sln for plants
TURGID, not burst just swollen b/c strong cell wall.
More SOLVENT than solute, water moves INTO cell
Isotonic solution for animals and plants
Animal: NORMAL
plants: SLIGHTLY TURGID
solute= solvent
Hypertonic solution for animals
SHRINK.
More SOLUTE than solvent.
Solute water moves OUT of cell
HyperTONIC sln for plants
PLASMOLYSED
more SOLUTE than solvent
Water moves OUT of cell
Leads to DETATCHMENT OF CELL MEMBRANCE FROM CELL WALL
What does active transport involve??
Movement of SOLUTES AGAINST A CONCENTRATION GRADIENTS
With use of ATP!!!!!!!
Lower concentration-> higher concentration
IN BULK TRANSPORTS explain EXOcytosis
Secretion of HORMONES + ENZYMES
ER->GOLGIAPP -> VESICLE -> secrete protein+ membrane fusion
In BULK Transport explain Endocytosis
Eg. PHAGOCYTOSIS( intake or bacteria/ food particles.
Food particle enters-> food particle surrounded by food vacuole
Protein enters-> coat protein with membrane-> coated VESICLE
Based on like dissolve lie principle does alcohol pass through membrane and where?
YEA it is hPHOBIC just like lipids so it can go right through pospholipid
What 4 types of subs can pass through PHOSPHLIPIPID BILAYER??
- Fat sol molecules
- HPHOBIC molecules
- NON polar molecules
- Small uncharged molecules (CO2/O2)
What needs to go through PROTEIN to enter BILAYE????!
Ions (Na/CAMa/Cl-) and POLAR MOLECULES (like glucose and water lul)
3 subs that CANNOT ENTER PIIPIDBLAYER
- Polysaccharide STARCH
- Polysaccharide SGLYCOGEN
- Protein Hamoglobin (2a, 2v polypeptides
What two transports use ATP
Active transport and Bulktransporta
What 5 factors enhance diffusion?
1.TEMP-higher
2. Conc diff- LARGER
3. SIZE molecules- smaller
4. A(sA) -larger
5 molecules that are LipoPHILIC in nature
3 types of PASSIVE TRANSPORT (region of high conce to low)
- simple diffusion (straight in pb)
- FASCILITATED DIFFUSION: protein carrier ( lipid INSOLUBLE SUBS) and protein channel (tunnel) (SMALL LIPId insoluble SOLUTES)
- OSMOSIS: aqua porin for WATER ONLY
3 steps explain how beetroot in alcohol cause solution to turn red
ALCOHOL IS HPHOBIC!!! Therefore can pass thru PB
- Alc destroys the membrane ( lose membrane permeability-> FULLY PERMEABLE)
- Red pigment in betroot cells leak out by DIFFUSION
- Sln turns red
Evidence of active transport for K+/Na+/Cl- as MAIN WAY FOR MINERAL UPTAKE
Ions in soul H20 is much less than that of cell sap concentration
Minerals are absorbed AGAINST THE CONCENTRATION GRADIENT
How graph shows effect of change in external conc of ion on concentration of ion within some plant cells
IONS are taken up by cells against a concentration gradient
Bec inside=29
Outside=1
uptake of ions in ACTIVE TRANSPORT requires..?
ATP
Why can only uptake of ions only occur in LIVING CELLS???
Only living cells can CELLULAR RESPIRATION
glucose–> ATP
