Transcript PASSIVE TRANSPORT Diffusion

• I went into a cell,
to get out of the rain… … _________________.
• I went into a cell,
and what did I see?…
• I went into a cell,
and said “who drives
this bus?”…
• I went into a cell,
to recover from a
spasm…
…
__________________.
… _________________.
• I went into the nucleus,
to ask how to get home…
• I went into a cell,
and stretching oh so far…
…__________________
_.
…__________________
• I went into a cell,
Trying not to be perplexed… .
• I went into a cell,
And said “who makes
proteins here?”…
…________________
__.
• I went into a cell,
and was feeling pretty fine…
• I went into a cell,
and was feeling pretty
nimble…
…___________________.
…__________________.
• I went into a plant cell,
to see how trees get so tall…
• I went into a plant cell,
“why’s it green I asked?”…
…__________________.
…____________________.
• I went into a plant cell,
to see plant cells store
food…
• So when you go
inside a cell…
• Just sing this song if
you ever feel
confusion…
…_______________.
…_______________.
…_______________.
Chpt. 5
HOMEOSTASIS & TRANSPORT
• cells regulate the movement of
materials across their
membranes
• maintain internal balance despite
changes in their environment
• This happens in ways that either
DON’T REQUIRE ENERGY
DO REQUIRE ENERGY
PASSIVE TRANSPORT
ACTIVE TRANSPORT
Uses NO ENERGY
Molecules move DOWN
or “with” their
concentration
gradient.
[HIGH]  [LOW]
Uses ENERGY
Molecules move UP
or “against” their
concentration
gradient.
[LOW]  [HIGH]
1. Diffusion
2. Osmosis
3. Facilitated Diffusion
1. Pump
2. Endocytosis
3. Exocytosis
PASSIVE TRANSPORT
Ex. Oxygen into your
cells from your
bloodstream, Carbon
dioxide out of your
cells to your
• Molecules move down
their concentration
gradient across a
membrane.
• High Concentration ->
Low Concentration.
• No ATP energy
required.
ACTIVE TRANSPORT
• Molecules move across the membrane
against their concentration gradient.
• Low Concentration -> High
Concentration.
• Requires ATP energy.
• Ex. Fructose into plant cells of a fruit.
DIFFUSION
• Movement of molecules from an area of
high concentration to an area of low
concentration.
What molecules diffuse
through/ across the cell
membrane?
• Oxygen & Carbon
Dioxide go through the
phospholipid bilayer.
• Others must go through
the protein channels.
OSMOSIS- the diffusion of water
• Diffusion of water
through a selectively
permeable membrane.
• Water moves through
a membrane from an
area of high water
concentration to an
area of low water
concentration.
TONICITYterm used to compare the solute
concentrations of two solutions
and predict the osmotic flow of
water between them.
• Isotonic- same
• Hypertonicmore solute & less water
• HypotonicLess solute & more
water
Water always flows from the hypOtonic to the hypertonic.
WHAT HAPPENS IF YOU PUT
A CELL INTO A ____
SOLUTION?
• HYPERTONIC
• HYPOTONIC
• ISOTONIC
swell
Stay same
shrivel
WHAT HAPPENS IF YOU PUT
A CELL INTO A ____
SOLUTION?
HYPOTONIC
swell
ISOTONIC
Stay same
HYPERTONIC
shrivel
PASSIVE TRANSPORT
Diffusion
through
phospholipid
bilayer
ex. O2 & CO2
Osmosis is the
diffusion of
Facilitated
Diffusion
- uses carrier
proteins
because the
molecule has a
charge & is too
big to fit
through the
bilayer.
Ex. glucose &
Diffusion through Ion
Channelscharged small
molecules or ions
travel through
membrane protein
tunnels
Ex.
-Na+, Cl-, K+, H2O
(aquaporins)
ACTIVE TRANSPORT
1. Cell membrane pumpUses carrier protein.
Moves materials up or
AGAINST their
concentration
gradient.
Ex. Sodium-potassium
pump in animals or the
hydrogen pump in
plants.
3 Na+ out
2 K+ in
1 ATP
1 ATP
1 H+ in
2. EndocytosisProcess by which
cells ingest
external fluid,
macromolecules,
and large
proteins, & other
cells!
ex. Pinocytosis
(drink)
Liquids & small
solutes
3.Exocytosisthe reverse of
endocytosis.
Release proteins
made on
ribosomes and
modified in the
golgi apparatus.