cells environment, movement across membranes

the regulations of intracellular movement

salt, ion concentration, nutrient and waste levels, glucose, carbon dioxide, temperature, ph

the cell membrane operates as a barrier between these functions

the regulations of intracellular movement

the cell membranes structure contains

a bilayer of phospholipids with embedded proteins

the cell membrane contains

macromolecules

the phospholipid bilayer is used to

regulate the entry and exit of solutes, in and out of the cell

the cell membrane is ____ and _____

semipermeable and allows some solutes to move easily than others

cholesterol is a vital part of

cells

cholesterol is used in cells to

give cells more structure where it is more fluid

phospholipids have

fatty acid tails that are hydrophobic

phosphate group heads are

hydrophilic

the phospholipids are brought together by the

chemical reactions of repelling water

phospholipids are arranged as

a bilayer

without the phospholipid bilayer, there would be

no membrane

the fluid mosaic bubble can have

things moved inside it

the fluid mosaic model is made up of

proteins and phospholipids

the phospholipids and proteins within the membrane can _____

move fluidly throughout the membrane and constantly change in position

a number of different ____ exist within the membrane of the cell

proteins

receptor proteins are used to

receive signals from other cells and sends messages into the cells

receptor proteins function by

binding chemical messengers, (hormones) to send messages

anchor proteins are to

ground the cell membrane and connects it to the cytoskeleton by holding it in place

there are ____ types of transport proteins

2

the 2 types of transport proteins are

carrier proteins and channel protein

carrier proteins are used to

pick up things and carriers them over

carrier proteins can recognise

specific substances, molecules and other things and selectively transport and let molecules through the cell membrane

channel proteins can

allow molecules to passively move across one side of the cell membrane to the other

transport proteins are used to

bring substances from one side to the other

transport proteins can be

outside, in between and inside the cell

diffusion and osmosis are passive and

don't require energy

active forms of movement across membranes requires

energy

simple diffusion is when

molecules spread from areas of high concentration to areas of lower concentration

diffusion will continue until

the concentration is almost equal

simple diffusion will occur down or along the

concentration gradient until equilibrium

simple diffusion is a

passive process

examples of simple diffusion are

O2, C02, breathing

during simple diffusion, molecules will

move from areas of high concentration to low concentration down a slope

even while in equilibrium, molecules will still continue to

move

simple diffusion does not require

proteins

facilitated diffusion is when

a protein helps molecules move

larger molecules are

unable to diffuse freely through membranes

some examples of molecules that are unable to diffuse freely are

glucose and amino acids

channel and carrier proteins must be used in order to

allow larger solutes to pass

facilitated diffusion is

passive and doesnt take much energy

osmosis is the process of the

diffusion of water (passive process)

osmosis is

the movement of water across a partially permeable membrane

water moves from areas of

LOW SOLUTE concentration to HIGH SOLUTE concentration

osmosis has nothing to do with the

concentration of water

the water moves instead of the salt because

the salt cannot move, and movement of salts/sugar would take too long

with a high concentration of solute, it must be balanced out by

water

osmosis is a _____ process

passive

if both sides are not equal, then there may be

detrimental effects

when in a hypertonic (less salt) solution, an animal cell and plant cell will:

burst and expand (due to the cell wall) respectively, due to the water trying to move OUT of the cell

when in hypertonic (more salt) solution, an animal and plant cell will:

wither and shrink respectively (cell wall maintains shape), as there is not enough water

water will ALWAYS:

move INTO cells that are placed into distilled water

water will always move into cells that are placed into distilled water, as

cells always have solute in their cytoplasm

water will always move from cells into sea water, which

has a high salt concentration

the difference in concentration between inside the cell (intracellular) and outside the cell (extracellular) is

concentration gradient

in the surface area to volume ratio is

the bigger the SA:V ratio, the better the diffusion rate will be, as smaller cells have a larger SA:V ratio

large molecules and charged molecules need

carrier or channel proteins

cells are small so that

things can go in and out faster, to be more efficient

high temperatures can

cause molecules to move faster and increases the rate of movement

cells can change shape when ______

cooked, because of a change in the chemical structure

a steep concentration gradient is

fast

a shallow concentration gradient is

slow

the larger the difference in solute on either side of the cell membrane

the faster the rate of diffusion will be

smaller cells allow for

a quick diffusion of nutrients

smaller cells have a

smaller surface area, smaller volume, but larger SA/V

larger cells have a

slower rate of diffusion

in larger cells, there are less

sites for exchanging material, compared to the volume to exchange

larger cells have a larger

surface area, larger volume, but smaller SA/V

active transport is the

transportation of substances from a region of lower solute concentration to a higher concentration

active transport is going

against a concentration gradient

active transport uses

energy in the body

active transport is done through the cells need to

accumulate high concentrations of molecules, such as ions, glucose and amino acids

carrier proteins are used to

pump substances AGAINST the gradient

ATP molecules provide

the energy needed for active transport

ATP is an

energy molecule

proteins use energy to

push things against the gradient, and energy helps change the shape of he protein

diffusion _____ -> _____

high -> low

active transport _______ -> _______

low -> high

osmosis _________ -> _________

low solute -> high solute