Transcript Cell Transport I

DO NOW
1. Get out your buffer lab
2. Which substance’s pH changed the most
when acid was added? What about when
base was added?
3. Why did the pH changes occur?
Homeostasis
The ability of an organism to adjust its
internal environment to keep it stable.
Where are WE?
Tissue
Organism
Cell Transport is
fueled by the
need of the cell
to maintain
homeostasis
Diffusion
Movement of particles from a high
concentration to a low concentration;
reach homeostasis
High
Low
What is concentration?
The amount of a substance
High concentration means there is a lot
present
External examples of diffusion
a. Food coloring and water
High concentration (amount of substance)
Low concentration
External examples of diffusion
b. Lotions/Perfume/Unpleasant odors in a
closed room
Substances that can diffuse across the
cell membrane
Certain substances can diffuse straight
across the phospholipid bilayer
Phospholipid bilayer
Examples of Diffusion
a. Oxygen and Carbon dioxide exchange in the
blood
Osmosis: Introductory Terms
Solution: A mixture of two or more
substances; both are completely dissolved
Osmosis: Introductory Terms
Solvent: The dissolver; usually a liquid
Osmosis: Introductory Terms
Solute: Disolvee; what is being dissolved
Osmosis
Movement of WATER from a high to a low
concentration
Hint:
a. Water will ALWAYS move to the higher
concentration of dissolved substances.
Hint:
b. Solute SUCKS solvent (water)!!!!
Solute
Water
Isotonic Solution
• Cell remains same
size
• Water moves in and
out at same rate
(time)
• The concentration
of dissolved
substances is equal
in and out of cell.
*RBC Video
*Elodea Video
Hypotonic Solution
• Cell swells
• Water moves in
• The higher
concentration of
dissolved
substances is
__________ the
cell.
*RBC Video
*Celery Video
Hypertonic Solution
• Cell shrinks
• Water moves out
• The higher
concentration of
dissolved
substances is
__________ the
cell.
*RBC Video
*Elodea Video
*Onion Video
Do Now
1. Explain what is happening in the picture
below. HINT: the white circles represent
water; black circles are sugar.
2. How can you recognize a hypotonic
environment?