BCLN – Rev. June, 2015
BIO 11 UNIT 07: Vascular Plants
Name: ___________________
Project 2: Plant Stomata Lab
Potential Credits:
/25
Project Goals:
 to observe and count stomata in leaf peals of different species of plants
 to investigate how stomata numbers are influenced by leaf type
Note:
Please note that this project has be adapted from the Biology Junction website at
http://www.biologyjunction.com/leaf_stomata_lab.htm.
Background:
Stomata are pores, typically found on the underside of the leaves, which allow gases to enter and
exit the leaves. Stomata can be opened or closed by the surrounding guard cells. The stomata will
open when guard cells swell with water and move apart or close when guard cells lose water and
move together.
Purpose:
The purpose of this lab is to become familiar with how to prepare and view specimens with a smart
phone microscope and to view and compare stomata structure and numbers from the leaves of
several species of plants.
Materials:
 smartphone
 smartphone microscope (you may build your own microscope following the instructions
given in Unit 7 Project 1: Make a Microscope or you may purchase a smartphone
microscope generally for under $30.00).
 leaves from 3 different species of plants (leaves must be at least 1 cm by 1 cm)
 clear nail polish
 transparent/clear tape (scotch tape)
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BCLN – Rev. June, 2015
BIO 11 UNIT 07: Vascular Plants
Procedure:
1.
2.
3.
4.
5.
6.
Collect all of the required material.
Pick one healthy leaf from each of the three plant species.
Paint a 1 cm x 1 cm square patch of clear nail polish on the underside of each leaf.
Allow the nail polish to dry completely!
Tape a piece of the transparent tape over the dried nail polish.
Gently pull on a corner of the tape to peel the nail polish patch off of the leaf. You should
end up with a leave impression (stomata and all) embedded in the nail polish and attached
to the tape.
7. Tape your leaf impression to either a glass microscope slide or a 2.5 cm x 7.5 cm piece of
clear plastic to make a "slide". You may use a clear sheet protector or plastic from
packaging or some other suitable source as long as it is clear.
8. Label your "slide" with the name of the plant species, both its common name and its
scientific name (you may need to look up the plant's scientific name).
9. Examine the leaf impression with the microscope using as high of a magnification as
possible.
10. Search for areas of the leaf impression that have many stomata yet no fingerprints, dirt,
major leaf veins of damaged leaf.
11. Take photographs of the stomata from at least three different regions of the leaf impression
for each of the plant species. Ensure that the photographs are taken at comparable
magnifications.
12. Present the photographs in the observation section below (either by printing and cutting
and pasting or preferably by directly importing the photographs into this document). Please
be sure to fill in the name of the plant in the blank spot left in the figure legend.
13. Count the number of stomata from at least 3 different photographs (of comparable
magnification) for each plant species. Record the numbers in the data table given below.
14. Complete the discussion portion of this project.
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BCLN – Rev. June, 2015
BIO 11 UNIT 07: Vascular Plants
Observations:
a.
Region 1 of Leaf Impression
b. Region 2 of Leaf Impression
c. Region 3 of Leaf Impression
Figure 1. Leaf Impression of a ______________________________________________________________ Leaf.
A leaf impression was created by painting clear nail polish on the underside of a leaf, allowing the nail polish to dry
and then placing tape over the dry polish. The tape and nail polish were then gently pulled away from the leaf to
create a leaf impression. The leaf impression was then viewed and photographed at maximum magnification using a
smartphone microscope. (3 marks)
a.
Region 1 of Leaf Impression
b. Region 2 of Leaf Impression
c. Region 3 of Leaf Impression
Figure 2. Leaf Impression of a _______________________________________________________________ Leaf.
A leaf impression was created by painting clear nail polish on the underside of a leaf, allowing the nail polish to dry
and then placing tape over the dry polish. The tape and nail polish were then gently pulled away from the leaf to
create a leaf impression. The leaf impression was then viewed and photographed at maximum magnification using a
smartphone microscope. (3 marks)
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BCLN – Rev. June, 2015
BIO 11 UNIT 07: Vascular Plants
a.
Region 1 of Leaf Impression
b. Region 2 of Leaf Impression
c. Region 3 of Leaf Impression
Figure 3. Leaf Impression of a _______________________________________________________________ Leaf.
A leaf impression was created by painting clear nail polish on the underside of a leaf, allowing the nail polish to dry
and then placing tape over the dry polish. The tape and nail polish were then gently pulled away from the leaf to
create a leaf impression. The leaf impression was then viewed and photographed at maximum magnification using a
smartphone microscope. (3 marks)
Table 1. Comparing Stomata Numbers from the Underside of Three Different Species of Plants. A leaf
impression was created by painting clear nail polish on the underside of a leaf, allowing the nail polish to dry and then
placing tape over the dry polish. The tape and nail polish were then gently pulled away from the leaf to create a leaf
impression. The leaf impression was then viewed and photographed at maximum magnification using a smartphone
microscope (refer to Figures 1-3 above). The number of stomata per photograph were then counted and recorded. (3
marks)
Plant Species
Common Name
Number of Stomata
Scientific Name
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Region 1
Region 2
Region 3
Average
BCLN – Rev. June, 2015
BIO 11 UNIT 07: Vascular Plants
Questions:
Please answer all questions in full sentences using proper spelling and grammar.
1. Did you use a homemade smartphone microscope or a commercial smartphone
microscope? (1 mark)
2. What is the maximum magnification of the smartphone microscope that you used? (1 mark)
3. Please explain the set-up that you used to take the photographs of your leaf impression
including noting lighting conditions, approximate magnification and the approximate
percentage of camera zoom (if any) that was used to take the photographs. (3 marks)
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BCLN – Rev. June, 2015
BIO 11 UNIT 07: Vascular Plants
4. How do the number of stomata compare in the three different species of plants? (3 marks)
5. What is a possible explanation of the various numbers of stomata that were observed
between the three different species of plants? You may have to do some background
research to answer this question well. (3 marks)
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BCLN – Rev. June, 2015
BIO 11 UNIT 07: Vascular Plants
6. Please identify at least two ways that you would improve upon this lab and explain how
and why you would make these improvements. (2 marks)
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