PEX-01-03

Exercise 1: Cell Transport Mechanisms and Permeability: Activity 3: Simulating Osmotic Pressure Lab Report
Pre-lab Quiz Results
You scored 75% by answering 3 out of 4 questions correctly.
1. Which of the following is true of osmosis?
You correctly answered: c. It is a type of diffusion.
2. Which of the following occurs when a hypertonic solution is added to cells?
You correctly answered: d. The cells shrink.
3. The variable that affects osmotic pressure is
You correctly answered: a. the concentration of nondiffusing solutes.
4. The net movement of water would be into the cell in a
Your answer : d. hypnotonic solution.
Correct answer: b. hypotonic solution.

01/20/14

page 1

Experiment Results
Predict Question:
Predict Question 1: What effect do you think increasing the Na+ Cl- concentration will have?
Your answer : a. increased osmotic pressure
Predict Question 2: What do you think will be the pressure result of the current experimental conditions?
Your answer : c. pressure above the left beaker
Stop & Think Questions:
Why do you think there is no pressure change?
You correctly answered: b. Sodium is able to diffuse through the pores.
Why do you think there was no pressure change?
You correctly answered: c. There is no net movement of water because the solute concentrations are the same.
Experiment Data:
Run Number
1
1
1
2
2
2
3
3
3
4
4
4
5
5
5
6
6
6
7
7
7

Solute
Na+ ClAlbumin
Glucose
Na+ ClAlbumin
Glucose
Na+ ClAlbumin
Glucose
Na+ ClAlbumin
Glucose
Na+ ClAlbumin
Glucose
Na+ ClAlbumin
Glucose
Na+ ClAlbumin
Glucose

MWCO
20
20
20
20
20
20
50
50
50
100
100
100
100
100
100
200
200
200
200
200
200

Start Conc. L
5.00
0.00
0.00
10.00
0.00
0.00
10.00
0.00
0.00
0.00
0.00
8.00
0.00
0.00
8.00
0.00
0.00
8.00
0.00
9.00
0.00

01/20/14

Pres. L
170
170
170
340
340
340
0
0
0
136
136
136
0
0
0
0
0
0
153
153
153

page 2

Start Conc. R