Graded Assignment
SCI203A: Biology | Unit 3 | Lessons 10 and 11: Laboratory: Determining the Rate of Diffusion
Name:
Date:
Graded Assignment
Lab Report
Answer the questions below. When you are finished, submit this assignment to your teacher by the due date for
full credit.
Completing Data Tables
(5 points)
1. Look at the sample cube and example data table. Then complete the data tables based on
your observations during Parts A and B of the lab.
Score
Sample Cube
Example Data Table: Calculations for Sample Cube
Surface Area (SA)
Sides
6
Length
4
Width
4
SA for Sample Cube
6 x 4 x 4 = 96
Volume (V)
Length
4
Width
4
Height
4
V for Sample Cube
4 x 4 x 4 = 64
Surface Area-toVolume Ratio (SA/V)
SA
96
V
64
SA/V for Sample Cube
96/64 = 1.5
Answer:
Data Table 1: Calculations for Cube 1
Surface Area (SA)
Sides
6
Length
1cm
Width
1cm
SA for Cube 1
6x1x1=6
Volume (V)
Length
1cm
Width
1cm
Height
1cm
V for Cube 1
1x1x1=1
SA
V
SA/V for Cube 1
Surface Area-toVolume Ratio (SA/V)
6cm
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1cm
6÷1=6
Page 1 of 4
Graded Assignment
SCI203A: Biology | Unit 3 | Lessons 10 and 11: Laboratory: Determining the Rate of Diffusion
Data Table 2: Calculations for Cube 2
Surface Area (SA)
Sides
6
Length
2cm
Width
2cm
SA for Cube 2
6x2x2=24
Volume (V)
Length
2cm
Width
2cm
Height
2cm
V for Cube 2
2x2x2=8
SA
V
SA/V for Cube 2
Surface Area-toVolume Ratio (SA/V)
24
24÷8=3
8
Data Table 3: Calculations for Cube 3
Surface Area (SA)
Sides
6
Length
2.5cm
Width
2.5cm
SA for Cube 3
6x2.5x2.5=37.5
Volume (V)
Length
2.5cm
Width
2.5cm
Height
2.5cm
V for Cube 3
2.5x2.5x2.5=15.625
SA
V
15.625
SA/V for Cube 3
37.5÷15.625=2.4cm
Surface Area-toVolume Ratio (SA/V)
37.5
Data Table 4: Diffusion Rates
Length
of Side
1 cm
2 cm
2.5 cm
Part A: 5 Minutes
Start Time:
Finish Time:
Distance Vinegar
Diffused
2mm
3mm
2.5mm
Diffusion Rate
(mm/minute)
2÷5=0.4mm/min
3÷5=0.6mm/min
2.5÷5=5mm/min
Part B: 10 Minutes
Start Time:
Finish Time:
Distance Vinegar
Diffusion Rate
Diffused
(mm/minute)
10mm
10÷10=1mm/min
4.5mm
4.5÷10=0.45mm/min
3mm
3÷10=0.3mm/min
Analysis Questions
(4 points)
2. Look at your data tables. List the cubes in order from largest to smallest. Then list them again
in order of the surface area-to-volume ratios, from the largest ratio to the smallest ratio.
Compare the lists.
Score
Answer:
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Page 2 of 4
Graded Assignment
SCI203A: Biology | Unit 3 | Lessons 10 and 11: Laboratory: Determining the Rate of Diffusion
Making Graphs
(2points)
3. Make a graph of your data, showing the distance vinegar diffused versus the surface area-tovolume ratio. Your graph should plot distance on the vertical axis, and the ratio on the
horizontal axis. Plot the points on your graph and connect them with a line.
Score
Answer:
(2points)
4. Make another graph, this time showing the diffusion rate (mm/minute) versus surface area-tovolume ratio. Plot the rate on the vertical axis, and the ratio on the horizontal axis.
Score
Answer:
(2 points)
5. Observe the two graphs you made, and analyze these results. What does the data tell you
about connection between the surface area-to-volume ratio and the diffusion rate?
Score
Answer:
( 8 points)
6. Did the vinegar diffuse all the way to the center of any of the cubes? If so, which ones? What
does this tell you about surface area-to-volume ratio and the diffusion rate? Please use the
data from the “Diffusion Rate” data table to support your answer.
Score
Answer:
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Copying or distributing without K12’s written consent is prohibited.
Page 3 of 4
Graded Assignment
SCI203A: Biology | Unit 3 | Lessons 10 and 11: Laboratory: Determining the Rate of Diffusion
Concluding Statement
(2 points)
7. Using what you have learned in this exercise, write a paragraph applying the concepts.
Describe a cell which effectively uses diffusion as a means to move materials in and out. Use
this information to suggest how being small helps cells survive, and being made of many
small cells helps large organisms maintain homeostasis.
Score
Answer:
Your Score
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Copying or distributing without K12’s written consent is prohibited.
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