Cellular Transport 0910

Cellular Transport
How do cells move nutrients, products

and wastes in and out of the cell?
Why is this traffic across the membrane

so important?
Cells are filled and surrounded
by watery fluid.
This fluid helps
solids move around
inside, outside the
cell and cross the
cell membrane.
Cell Membrane
The cell membrane
controls what moves
in and out of the cell.
Semi-permeable membrane
Cell membranes only allow
some solutes (solids) to
move across it.
Movement across the

membrane depends on size
and type of the solute
(solid).
Membranes are just so beautiful!!!!!
Types of Transport
Low Down the

High
concentration concentration gradient
concentration
High Up the
Low concentration concentration gradient
concentration
Summary: Types of Transport
 Passive Transport  Active Transport
 Molecules move from area  Molecules move from area
of high concentration to of low concentration to
area of low concentration area of high concentration
 Movement is down the  Movement is up the
concentration gradient concentration gradient
 No energy needed  Energy is required (ATP)
 Small molecules such as  Large molecules, ions
H2O, O2 and CO2
Diffusion – molecules move from area of
high concentration to area of low concentration.
Osmosis – water moves across membranes
(diffuses) to where there is less water.
Concentrations affect Osmosis
Water moves
out of the cell
Water moves
across
Water
membrane
moves into
(in/out) at
the cell
equal rates.
Red Blood Cells
in Hypertonic solution (video)
Plants and Osmosis
Hypertonic solution (video)
Concentrations affect osmosis
higher amount of equal amount of lower amount of

solute outside solute in and out solute outside
cells of cells cells
Solution is made of solutes dissolved
in a liquid or gas.
Let’s Review Hypertonic Solution = high amount of

solutes
Hypotonic Solution = low amount of

solutes
Isotonic Solution = equal amount of

solutes
Dynamic Equilibrium is reached

when solutes and water move
across a membrane at equal rates
because concentrations are equal
(isotonic).
Homeostasis = all living systems need

to maintain perfect concentrations
inside each cell
Test your knowledge
On your left side, number 1-14 (short

answer)
15 and 16 Extended answers required

1. Which side is hypertonic? A B A B
Lower Higher
concentration concentration Same concentration
2. Why? of solute (sugar) of sugar of sugar
3. Can the solutes fit across

the membrane?
4. How can you describe the

membrane since it is very Selectively
selective about what can permeable
Water molecules
mem-
cluster around
brane: sugar mole-
move across?
sugar molecules
cules cannot pass
through pores, but
water molecules can
More free water

Fewer free water
5. How can both sides reach molecules (higher
concentration)
molecules (lower
concentration)
equilibrium? Osmosis

Water moves from an area of higher
free water concentration to an area
of lower free water concentration
ENVIRONMENT NaCL (salt is ionic,
10% NaCL cannot pass through
membrane without energy)
90% H2O
CELL ?
10% NaCL
90% H2O
6. What is the direction of water movement?

_________
7. Describe the solution outside the cell. ________
8. Describe the solution inside the cell. __________
10% NaCL
90% H2O
CELL
?
20% NaCL
80% H2O
9. What is the direction of water movement?________

11.Describe the solution inside the cell. __________
15% NaCl
85% H2O
CELL ?
5% NaCl
95% H2O
12. What is the direction of water movement?_______

14. Describe the solution inside the cell. __________
15. How do cell move nutrients, products and wastes in
and out of the cell?
16. Why is this traffic across the membrane so
important?
Demo Lab
Materials Procedure
- Celery sticks in
different salt
solutions???
- Iodine solution /
starch solution???
- Potato cores in
different salt
solutions???
Cell membrane tendency of any molecule to spread out into available space
Selectively permeable diffusion of a substance across a biological membrane
Hypotonic These help transport things across the membrane

lower concentration of solutes
Hypertonic
passage of molecules and ions with transport proteins across a
Isotonic membrane down the concentration gradient
movement of a substance against its concentration gradient with
Passive transport the help of cellular energy
Diffusion Membrane only allows certain things across

Barrier made up of phospholipids and proteins that controls what
Concentration gradient enters and exits the cell
Solution When there are two different concentrations across a membrane.
Molecules always move from high to low concentration without
Solute energy (ATP)
equal concentrations of solutes
Equilibrium/Homeostasis
the diffusion of water across a selectively permeable membrane
Active transport
control of water balance
Membrane proteins
Combination of a solvent and a solute equally mixed
Osmosis
Molecule used in living systems for energy
Osmoregulation
State where molecules move across the membrane at equal rates
Facilitated Diffusion
A substance being dissolved in another
ATP
higher concentration of solutes

Cellular Transport 0910

Uploaded by

Copyright:

Available Formats

Cellular Transport 0910

Uploaded by

Document Information

Original Description:

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Cellular Transport 0910

Uploaded by

Copyright:

Available Formats

Cellular Transport

How do cells move nutrients, products

Why is this traffic across the membrane

Movement across the

Low Down the

higher amount of equal amount of lower amount of

Let’s Review Hypertonic Solution = high amount of

Hypotonic Solution = low amount of

Isotonic Solution = equal amount of

Dynamic Equilibrium is reached

Homeostasis = all living systems need

On your left side, number 1-14 (short

15 and 16 Extended answers required

3. Can the solutes fit across

4. How can you describe the

More free water

6. What is the direction of water movement?

9. What is the direction of water movement?________

12. What is the direction of water movement?_______

Selectively permeable diffusion of a substance across a biological membrane

Hypotonic These help transport things across the membrane

Diffusion Membrane only allows certain things across

You might also like