Transcript Diffusion:Active Transport

Transport of Molecules
concentration

A
B
Where is there
a higher
concentration
of yellow dots?
DIFFUSION

A
B
Tendency for
molecules to
move from an
area of high
concentration to
an area of low
concentration.
Transport of Molecules
WHAT IS HAPPENING - EXPLAIN THIS TO
THE PERSON SITTING NEXT TO YOU…
DIFFUSION

Tendency for
molecules to
move from an
area of high
concentration to
an area of low
concentration.
DIFFUSION through a
semi-permeable membrane

membranes act
as filters.
DIFFUSION through a
semi-permeable membrane

SOLUTE

SOLVENT
particle
that
dissolves
substance in which
another substance is
dissolved
DIFFUSION through a
semipermeable membrane

Tendency for
molecules
to move from an
area of high
concentration to a
an area of low
concentration
solution
IODINE + STARCH ->

PURPLE
DIFFUSION through a
semipermeable membrane

Tendency for
molecules
to move from
hypertonic
solution to a
hypotonic solution
Hypertonic = HIGH solute
concentration
compared to “X” side
Hypotonic = low solute
concentration compared to “X”
side
outside
WE HAVE BEEN MOVING
SOLUTE MOLECULES…..
Moving the SOLVENT
What
is
next?

OSMOSIS through a
semipermeable membrane

Tendency for
WATER
to move from ???
solution to a ???
solution
osmosis

Tendency for
WATER
MOLECULES to
move from
hypotonic
solution to a
hypertonic
solution
DIFFUSION
OSMOSIS
think of passive transport like
going down a slide…
think of facilitated diffusion like
going down a slide… with help
of proteins
It
just
goes!
going from HIGH to low
requires no energy…
Still PASSIVE….
What is
different?
think of DIFFUSION like going
down a slide…
Going from HIGH to low
requires no energy…
What happens in plant cells?

OSMOSIS???
What happens in plant cells?

Remember, they
have a CELL WALL
What happens in plant cells?

the pressure of
the cell contents
against the cell
wall, in plant cells,
determined by the
water content of
the vacuole
What happens in plant cells?

the pressure of
the cell
contents
against the cell
wall, in plant
cells,
determined by
the water
content of the
Osmosis in cells w/ walls
Isotonic is not good enough!
TURGID vs. FLACID
with salt
CELL
CELL
MEMBRAN WALL
E
w/ distilled H2O
CELL
MEMBRAN
E
ISOTONIC
Red
Blood
Cells
pertonic inside the cell
HY
potonic inside the cell
HY
Are these words dealing with the
CELL…. Or the SOLUTION outside
the cell?
NOT
PASSIVE!!
Endocytosis
Endocytosis {Endo (within) cytosis (cell) } is a
process in which a substance gains entry into
a cell without passing through the cell
membrane. This process is subdivided into
three different types:
Active Transport = [low] to [high]
ATP
think of active transport like
going up a slide…
think of active transport like
going up a slide…
going from low to HIGH
requires a lot of energy…
think of active transport like
going up a slide…
going from low to HIGH
requires a lot of energy…
phagocytosis
Phagocytosiscell eating
pinocytosiscell drinking
exocytosiscell vomiting