Active Transport



Identify the type
of solution
Describe what
will move, and
where
Explain how the
cell’s volume will
change
1.
2.
A cell contains a solution
that is 88% water, and it is
sitting in a solution that is
20% water.
A cell contains a solution
that is 43% sugar, and it is
sitting in a solution that is
99% sugar.
When you are done, begin to read
through the Egg Lab packet.
Agenda





Catalyst
HW review
Egg Lab!
Active Transport
EQ
Homework Review

http://www.coolschool.ca/lor/BI12/unit
4/U04L06/rbc.html
HYPOTONIC
ISOTONIC
HYPERTONIC
“LYSIS”
Yesterday…
We learned about OSMOSIS!
Egg Lab – Day 1


An egg can be thought of as a big cell. After the
shell is removed (with vinegar), it is a partially
permeable membrane.
Putting this egg in a hyper/hypotonic solution will
cause osmosis to occur.
Egg Lab – Day 1
SET UP:
1.
Observe each egg. Record your observations in Data
Table 2.
2.
Calculate the mass of each egg. Record this mass in Data
Table 1.
3.
Label one beaker A and one beaker B. Put one egg in
each.
4.
Add enough acetic acid to the beaker so that you are
completely covering the egg.
5.
In Data Table 2, record detailed observations of the eggs.
How do you use a triple-beam balance?



Calibrate using knob on the left! Make sure balance
is pointing at 0 before you start.
Put object on metal balance.
Start with the highest beam (100 g) increments.
Move it over one by one notch until the balance
goes below 0. Do this for each beam until you have
you balance at 0.
What if we want to take the mass of
an egg?

It might roll off and die!

Correct method:
 Take
mass of the beaker. (WRITE IT DOWN – Data
Table 1)
 Take the mass of the beaker and the egg inside it.
 Subtract the first mass from the 2nd to get the mass of
the egg.
 Mass
of Beaker+Egg – Mass of Beaker = Mass of Egg
Egg Lab – Day 1
QUESTION: Will an unshelled egg increase or
decrease in mass after being placed overnight in
corn syrup or water?
Egg Lab – Day 1
HYPOTHESIS: Formulate two hypotheses, one for
putting an egg in water, the other for putting an
egg in corn syrup. (Formulate means “create.”)
Example:
CHOOSE ONE
1. If the egg is placed in water, then it will increase/decrease in mass because
____________.
2. If the egg is placed in corn syrup, then it will increase/decrease in mass
because ____________.
Egg Lab – Day 1
VARIABLES:
 Identify your INDEPENDENT and DEPENDENT
variables.
 Identify at least 2 CONSTANTS.
REMEMBER: Variables are categories, not specific
things!
Objectives

By the end of the period,
SWBAT…
Compare
active and passive
transport
Identify whether cellular transport is
diffusion, active transport, or
osmosis
Passive Transport

Key Point #1: Passive transport takes no
energy and always moves towards
equilibrium.
 The
goal is equal concentration
 High  Low concentration
 Happens naturally (no energy)
 BOTH diffusion AND osmosis are passive
transport

In DIFFUSION
The solutes are permeable
to the membrane and move
H  L.
In OSMOSIS

Only water is permeable
to the membrane.
75%
water
20%
water
Active Transport




Key Point #2: Active transport
takes energy to move all solutes in
or out of the cell.
The goal is to move against equilibrium
Low  High concentration
Happens on purpose (takes energy)
In ACTIVE
TRANSPORT

The solutes are permeable to
the membrane and move L  H
Active Transport

Why would the cell do this?
To
store food inside the cell
To eliminate wastes
To get rid of toxins
NO
ENERGY
Comparing the Three
DIFFUSION
PASSIVE
TRANSPORT OSMOSIS
ACTIVE
TRANSPORT
SOLUTES
SOLUTES
WATER
EQUILBRIUM
EQUILBRIUM
ENERGY
Helpful Hints

How can you tell if something is active or passive?
How do you know if it diffusion or osmosis?

Ask yourself:

 Is
the solute moving, or is water moving?
 What is permeable to the membrane?
 Are we moving H  L or L  H?
Guided Practice

State whether this is Active
Transport or Passive Transport
Active or Passive?
Active or Passive?
Active or Passive?

Water moving to equalize concentrations
Active or Passive?

Cell uses energy to get as much sugar as
possible
Active or Passive?

Happens naturally with no use of energy
Active or Passive?

ALL solutes being moved out of the cell
Active or Passive?

Takes energy
Active or Passive?

Moving toward equilibrium
Changing Gears

Now I will give you two cells. I will tell you what is
moving and where. You tell me if it is DIFFUSION,
OSMOSIS, OR ACTIVE TRANSPORT.
If solutes are moving from L  R
If solutes are moving from L  R
If water is moving from R  L
Water is moving from
inside  outside
A cell has a 40% sugar concentration
inside is in a solution of 50% sugar
concentration
 HINT: IT MIGHT HELP YOU TO DRAW
THE SITUATION

Solutes are moving from
inside  outside

A cell has a 10% sugar concentration
inside is in a solution of 50% sugar
concentration
Solutes are moving from
outside  inside

A cell has a 10% sugar concentration
inside is in a solution of 80% sugar
concentration
Solutes are moving from
outside  inside

A cell has a 40% sugar concentration
inside is in a solution of 20% sugar
concentration
Key Point Wrap-Up

Key Point #1: Passive transport takes
no energy and always moves towards
equilibrium.
Both

diffusion and osmosis
Key Point #2: Active transport takes
energy to move all solutes in or out of
the cell.
Exit Question
1.
Match each of the following statements to
either ACTIVE or PASSIVE transport. (You do
not have to write complete sentences!)
 (1)
Requires energy
 (2) Movement of solute or solvent in/out of a cell
 (3) Moves toward equilibrium
2.
A cell containing 20% sugar solution is
placed in 80% sugar solution. What will
happen if ACTIVE transport occurs?