Active Transport

1. A cell contains a solution that is 88% water, and it is sitting in a solution that is 20% water.

2. 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.

Identify the type of solution

Describe what will move, and where

Explain how the cell’s volume will change

Identify the type of solution

Describe what will move, and where

Explain how the cell’s volume will change

Agenda

Catalyst HW review Egg Lab! Active Transport EQ

Homework Review

http://www.coolschool.ca/lor/BI12/unit4/U04L06/rbc.html

HYPOTONICHYPOTONIC ISOTONICISOTONIC HYPERTONICHYPERTONIC

“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:

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 ____________.

CHOOSE ONE

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

Comparing the Three

DIFFUSION

ACTIVE TRANSPORT

PASSIVE TRANSPORT

OSMOSIS

SOLUTES

WATER

EQUILBRIUM

NO ENERGY

SOLUTES

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 outsideA 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 outsideA cell has a 10% sugar

concentration inside is in a solution of 50% sugar concentration

Solutes are moving from outside insideA cell has a 10% sugar

concentration inside is in a solution of 80% sugar concentration

Solutes are moving from outside insideA 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 Question1. 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?