Transcript Cellular Transport

Cellular Transport
Do Your Cells
Eat and Drink?
• Cells must take in
water and
nutrients in order
to function.
Mmm…..
What part of the cell
allows it to take in
nutrients and water?
Or……
The CELL
Also
knownMEMBRANE!!!!!!
as…..
PHOSPHOLIPID BILAYER
PLASMA MEMBRANE
What is the Cell
Membrane Made Of?
• Proteins and phospholipids
What are the Proteins
in the Cell Membrane?
Carrier
Channel
Peripheral
Integral
SO….. How DO Your
Cells Eat, Drink and be
Merry?
Cells move substances
through the cell membrane by
a process called transport
• Two Types of Transport:
–Passive Transport
–Active Transport
What is
Passive Transport?
• Diffusion
• Requires no energy from cell.
• Molecules move from
high concentration to
low concentration.
• Molecules move with the
concentration gradient.
Why?
• To reach equilibrium
–Equal movement of molecules
in all directions (into and out of
the cell).
Diffusion
• How does it work?
Osmosis
• The diffusion of water across a
semi-permeable membrane.
–“Water wants to water “stuff”
down”
“Salt Sucks”
What would happen to
the animal cells in each
beaker?
100% Distilled
Water
80% Water
20% Dissolved
Substances
70% Water
30% Dissolved
Substances
Which way did the
water move?
Hypotonic solution
Hypertonic cell
80% H2O
20% “stuff”
100% Distilled Water
0% dissolved
substances
Why did the cell
get so big?
Which way did the
water move?
Isotonic solution
Isotonic cell
80% H2O
20% “stuff”
80% Water
20% Dissolved
Substances
Why did the cell
stay the same
size?
Which way did the
water move?
Hypertonic solution
Hypotonic cell
80% H2O
20% “stuff”
70% Water
30% Dissolved
Substances
Why did the cell get
so small?
• Let’s look at what happens to
your blood cells in the three
different solutions:
–Isotonic (equal)
–Hypertonic (high)
–Hypotonic (low)
Turgor pressure
Onion cells
Osmosis in plants
Facilitated Diffusion
• Diffusion of large or polar
molecule through protein
channels.
–“Helped Diffusion”
REVIEW
1. What are the characteristics of
passive transport?
2. Explain diffusion. Why does it
occur?
3. Explain osmosis. Why does it
occur?
4. What is the role of the channel
protein in facilitated diffusion?
Even MORE Review!
1. What happens to an animal cell
when there are more dissolved
substances on the outside of
the cell?
2. The inside?
3. When there are equal
amounts?
Active Transport
How is Active
Transport different?
1. Active transport requires energy.
2. Molecules move from low
concentration to high
concentration
3. Molecules move against
concentration gradient.
What is this cell doing?
Endocytosis
• Cells bring in large particles using
the cell membrane
– There are 2 types:
• Phagocytosis
• Pinocytosis
• Channel proteins are used to bring in
large molecules.
Phagocytosis
Amoeba
• Your white bloods cells also do this.
• This is the ingestion of large particles.
Pinocytosis
• Tiny pockets form along cell membrane, and
pinch off into vacuoles inside the cell.
Sometimes called “Cell Drinking”
Exocytosis
• This is how the cell gets rid of waste.
REVIEW
1. How is Active transport different
from passive? Complete the chart.
2. What part of the cell is used to
bring in particles?
3. How does a cell (including white
blood cells) take in LARGE
particles?
4. How does a cell take in small or
liquid particles?