Cell Membrane and Cell Transport

does not require energy because it moves with the concentration gradient, (high to low)

requires energy, goes from low to high concentration so against the concentration gradient

molecules move from more (high) to less(low) concentrated area until equilibirium is reached, small nonpolar molecules

diffusion of water through a selectivly permeable membrane

pressure due to water

diffusion with the help of carrier/channel proteins aka selective transport, hydrophilic and ions t pass through membrane

diffusion, osmosis, facilitated diffusion (selective transport)

sodium pottasium pump, proton pump, exocytosis, endocytosis

large molecules transported out, vesicle fuses with cell membrane

large molecules transported in, vesicle forms from cell membrane

the cell membane pushing into the cell to accept the molecule (in exocytosis and endocytosis)

cell drinking, molecules takeninto cell wall with large amounts of liquid with it

solid molecules taken in by cell (bacteria engulfed by white blood cells)

receptor proteins figure out the need the molecules floating around and they attach to the recpetor protein and are brought intot he cell through endocytosis

both directions in and out of the cell

cells smart why spend energy bringing it in or pushing it out j to do the opposite and spend more energy

sensing electrical signals, how nerve cells communicate

sensing chemical signals, ex. liver cells sensing blood glucoe levels high so they open channel proteins

movement of water

high water to low water

low solute to high solute

atp→carbs→lipids

the highest energy bond so it breaks causing atp to change to adp when energy is needed

reversible process changing back and forth based on whats needed

biocatalysts

energy being absorbed from enviornment, (endothermic with thermal energy)

energy being released (exothermic with thermal energy)

the reaction time plateus and no longer increases because the solution is saturated with subrates and adding more will no longer increase reaction rate

the active site

have an active site and then an allosteric site where teh product of the active site fits and then after the reaction happens in the allosteric sit ehte active site changes shape so that the enzyme is inactive, when all of the product is used up the enzyme becomes active again and changes the shape of the active site back to what the subrate fits into

a→b

b→c

c→d

d→e

if b→c stops working them the chain of reactions stops happening and the biochem pathway goes away and there will be excess b but not c,d, or e

b,c,d are intermediates while a is the reactant and e is the product

multiple enzymes working on biochem pathway

1 ezyme with mulitple active sites that does the entire biochem pathway

secondary active transport, uses energy from electrochemical gradient, transport 2 diff ions across membrane through proteins

2 diff ions same direction

2 diff ions diff directions

polarized

type of concentration gradient, electrical difference across membrane

electrical potential diff(voltage) across membrane

total solute concentration

help large quantities of water move via aquaporins

mesaurement of the relative concentrations of solute b/w 2 solutions (inside and outside of cell)

more solute less solvent

less solute more solvent

cell shrinks

cell swell

when cell bursts

tendency water to move through osmosis

pass through the membrane

free living aerobic prokaryote engulfed by anaerobic cell through endocytosis but it didnt get ingested and it eventually lost its independence, origin of mitocondria and chloroplast, they both have double membrane and their own copies of dna and ribosomes

plasma membrane folding

intial starting energy, lowered by enzymes

typically require less activation energy

typically require more

tertiary shape

• inreased speed of molecular movement

• increased frequency of enzyme subtrate collisions

decreases reaction time bc less substrate enzymes collisions

pH

themore subrate the more product and once there isalot of product it takes up space so lower chance of enzyme substrate collion

molecules can bind reversibly or irrversibly to the active site of the enzymes, competes with the normal substrate for enzymes active site

the reactions are slow

the enzymes function is prevented

bind to allosteric site, not active site which causes the enzyme to change shape of the original active site preventing enzyme function

physical or chemical sources that are changed into somthing usable

• every energy transfer increases disorder

• living cells are never at equilibrium there is always a constant flow of materials in and out

• cells manage energy resources by energy coupling, energy releasing processes drive energy storing processes

inorganic nonprotein helpers (Fe, Zn, Cu)

organic helpers (vitamins)

energy can neither be created nor destroyed only changed

use couled channel proteins to bring it back in using facilited diffusion

chem energy from transport, cell wont spend energy to bring back protons diffuse back in with atp

plant cell in isotonic solution

plant cell in hypotonic solution but doesnt lyse or burst bc of cell wall (turgor pressure)

0.851, (saline)

how water is forced up xylem

water loss through xylem

transport of sugar through the phloem

small drops of sap (water and minerals) ooze from the leaf tip due to root pressure

helps prevent water loss, small hair on leaf and leaf surface

guard cells

high, low psi

decreases

increases