Passive Transport Notes

Study this information for the AIR test

1. Passive Passive
Transport NotesTransport Notes

2. TransportTransport
Passive TransportPassive Transport – movement of – movement of
substances down their concentration substances down their concentration
gradient (high concentration to low gradient (high concentration to low
concentration); no energy required.concentration); no energy required.

3. Passive TransportPassive Transport
4 types of passive transports4 types of passive transports::
1. Diffusion1. Diffusion
2. Osmosis2. Osmosis
3. Facilitated Diffusion3. Facilitated Diffusion
4. Diffusion through Ion Channels4. Diffusion through Ion Channels

4. DiffusionDiffusion
DiffusionDiffusion – is the – is the
movement of movement of
molecules from an molecules from an
area of high area of high
concentration to an concentration to an
area of lower area of lower
concentration.concentration.

6. EquilibriumEquilibrium
EquilibriumEquilibrium – is the state when the – is the state when the
concentration of molecules are equal on concentration of molecules are equal on
both sides of the membrane.both sides of the membrane.

8. OsmosisOsmosis
OsmosisOsmosis – is the – is the
process of process of waterwater
diffusing across a diffusing across a
cell membrane from cell membrane from
an area of high an area of high
concentration to an concentration to an
area of lower area of lower
concentration.concentration.

10. OsmosisOsmosis
Water moves down its concentration Water moves down its concentration
gradient and does not require energy, so gradient and does not require energy, so
it is a type of passive transport.it is a type of passive transport.

11. Passive TransportsPassive Transports
To fully understand how diffusion and To fully understand how diffusion and
osmosis works in a cell, you need to osmosis works in a cell, you need to
know a few vocabulary words that you know a few vocabulary words that you
should have learned last year.should have learned last year.

12. SolutionsSolutions
What is a solution?What is a solution?
SolutionSolution – is a – is a
mixture in which one mixture in which one
or more substances or more substances
are equally distributed are equally distributed
in another substance.in another substance.
Ex. Pop, saltwater, Ex. Pop, saltwater,
sugarwatersugarwater

13. Parts of Parts of
SolutionSolution
2 parts of a solution2 parts of a solution::
1. Solute1. Solute – is the – is the
substance being substance being
dissolved by the dissolved by the
solvent.solvent.
Ex. Salt or sugarEx. Salt or sugar
2. Solvent2. Solvent – is the – is the
substance that substance that
dissolves the solutedissolves the solute
Ex. Water Ex. Water

14. MixturesMixtures
Solutions can be made of various Solutions can be made of various
proportions of solutes and solvents.proportions of solutes and solvents.
ConcentrationConcentration – the amount of solute – the amount of solute
dissolved in a fixed amount of solution.dissolved in a fixed amount of solution.
Ex: 1g. of salt in 10g. of water= 10% salt Ex: 1g. of salt in 10g. of water= 10% salt
solutionsolution
Saturated SolutionSaturated Solution – is when no more – is when no more
solute can be dissolved. The solute just solute can be dissolved. The solute just
lays at the bottom of the cup.lays at the bottom of the cup.

15. Passive TransportsPassive Transports
A big part of understanding homeostasis A big part of understanding homeostasis
(body is at equilibrium), is understanding (body is at equilibrium), is understanding
how a cell will react in different solutions.how a cell will react in different solutions.
So, we have special names for solutions So, we have special names for solutions
in how they affect cells.in how they affect cells.

16. Types of SolutionsTypes of Solutions
HypotonicHypotonic – when – when
the concentration of the concentration of
solutes outside the solutes outside the
cell is lower than the cell is lower than the
concentration of concentration of
solutes inside the solutes inside the
cell.cell.
Ex. Cells in a beaker Ex. Cells in a beaker
of pure water.of pure water.

17. Types of SolutionsTypes of Solutions
In a hypotonic solution the water in the In a hypotonic solution the water in the
solution would move into the cell to reach solution would move into the cell to reach
equilibrium.equilibrium.
This could cause the cell to burst and is This could cause the cell to burst and is
why your hands get wrinkly when bathing why your hands get wrinkly when bathing
for a long time.for a long time.

18. Types of SolutionsTypes of Solutions
HypertonicHypertonic – when – when
the concentration of the concentration of
solute outside the solute outside the
cell is higher than the cell is higher than the
concentration inside concentration inside
the cell.the cell.
Ex. A cell in a beaker Ex. A cell in a beaker
of saltwater.of saltwater.

19. Types of SolutionsTypes of Solutions
The water will move out of the cell and The water will move out of the cell and
into the solution to reach equilibrium.into the solution to reach equilibrium.
This may cause the cell to shrivel up and This may cause the cell to shrivel up and
become dehydrated.become dehydrated.

20. Types of SolutionsTypes of Solutions
IsotonicIsotonic – when the – when the
concentration of concentration of
solutes outside and solutes outside and
inside the cell are inside the cell are
equal.equal.
Same amount of salt Same amount of salt
outside and inside outside and inside
the cell.the cell.
This is the goal of This is the goal of
every cell.every cell.
Water will move both Water will move both
ways.ways.

22. VocabularyVocabulary
Turgor PressureTurgor Pressure - is the pressure - is the pressure
inside the cells that give organisms there inside the cells that give organisms there
form.form.
Organisms without turgor pressure will Organisms without turgor pressure will
have no form out of water.have no form out of water.
Cells loose turgor pressure when they Cells loose turgor pressure when they
loose water.loose water.

23. Turgor PressureTurgor Pressure
This is why plants wilt in the summer, This is why plants wilt in the summer,
because they have lost water due to dry because they have lost water due to dry
weather.weather.
The water evaporates out of the vacuole The water evaporates out of the vacuole
(storage in plant cells) and with no water (storage in plant cells) and with no water
there is no turgor pressure.there is no turgor pressure.

24. Facilitated DiffusionFacilitated Diffusion
Facilitated DiffusionFacilitated Diffusion
– is the movement of – is the movement of
molecules through molecules through
the membrane by the membrane by
using proteins.using proteins.
Carrier ProteinsCarrier Proteins – –
are the proteins used are the proteins used
in facilitated in facilitated
diffusion.diffusion.

26. Diffusion Diffusion ThroughThrough Ion Ion
ChannelChannel
Is the process of transporting ions Is the process of transporting ions
through membrane proteins known as through membrane proteins known as
ion channels.ion channels.
Ex. ions are Sodium, potassium, calcium, Ex. ions are Sodium, potassium, calcium,
and chloride.and chloride.
These ions use the proteins as a channel These ions use the proteins as a channel
to move through the membrane and into to move through the membrane and into
the cell.the cell.

27. Ion ChannelsIon Channels
Each type of ion Each type of ion
channel is usually channel is usually
specific for one type specific for one type
of ion.of ion.
Most channels allow Most channels allow
Na to pass through.Na to pass through.

28. Passive Transport Passive Transport
Question????Question????
If you put a piece of potato into a beaker
of distilled water and another piece of
potato in a beaker of saltwater. The
piece of potato in the freshwater
becomes very stiff, while the piece of
potato in the saltwater became very
flexible.
In complete sentences explain why the
potato in the freshwater became stiff and
the potato in the salt water became
flexible. (4 points)

29. Answer to Passive Answer to Passive
Transport QuestionTransport Question
The piece of potato that was put into distilled water The piece of potato that was put into distilled water
swelled up and stiffened, because of an increase in swelled up and stiffened, because of an increase in
turgor pressure. The turgor pressure increased turgor pressure. The turgor pressure increased
because the potato was in a hypotonic solution which because the potato was in a hypotonic solution which
caused water to move into the potato by a process caused water to move into the potato by a process
called osmosis. The piece of potato that was put into called osmosis. The piece of potato that was put into
the saltwater shrank and became flexible, because of a the saltwater shrank and became flexible, because of a
loss of turgor pressure. The turgor pressure was lost, loss of turgor pressure. The turgor pressure was lost,
because the potato was in a hypertonic solution which because the potato was in a hypertonic solution which
caused water to move out of the potato by a process caused water to move out of the potato by a process
called osmosis.called osmosis.