Welcome to the Timber Ridge Magnet School/Grove Elementary School Second Grade Science Fair Collaborative
 

Below you will find two second grade projects that are being conducted by the two schools named above. 

The projects will begin on Monday, February 23, 1998. Look below for a daily journal to keep you updated on the results.   
 
 

 

What is Stomata?

 

Question:   What side of a plant leaf takes in gases?

 

Hypothesis:  Ten (10) students say the top of the leaf takes in gases because when rain and watering cans water plants it comes from above and hits the top of the plant leaves first. Ten (10) say  the bottom of the leaf takes in gases because after observing the leaves from each plant the bottom of the leaves were more veiny  and the skin of the bottom leaves seemed thinner.  The top of the plant  leaf had a thicker, waxy covering and it looked like water would be hard to get through it.

 

Materials:  Two varieties of plants 

Vaseline 
A  Camera

 

Procedure:  Coat the top of four leaves from each plant with a heavy layer of Vaseline. 

Coat the underside of four leaves from each plant with a heavy layer of  Vaseline. 
Observe the leaves daily for one week. 
Is there any difference in the two sets of leaves?

 

Results:       Three of the four  leaves that had Vaseline on the underside, died. Only one leaf with vaseline on the top died. Therefore, we believe that plant leaves take  in gases from the bottom, not the top, of each leaf.

 

Why:           Openings on the underside of plant leaves called stomata allow gases to  move into and out of the leaves.  The vaseline plugged the openings and the leaf was not able to receive the necessary carbon dioxide gas or eliminate excess oxygen gas.

 

 

Observation Journal  Day One 
Text 
Monday, February  23, 1998  
Each student closely observed each plant.  
 
The students observed no change in both plants by the end of the day. 

The Vaseline made the leaves heavier and each plants' appearance changed after the vaseline was applied. 
 
 

Observation Journal - Day One 
Monday, February 23, 1998  
The students did not notice much change in the leaves with Vaseline on the tops or the bottoms. The class felt that the leaves with Vaseline were shiny and the plain leaves were dull. They also discussed that the leaves that were treated were darker in color. We needed to discuss that the leaves were originally light on the under side and darker on the top because they felt this was a change caused by the Vaseline.

 

Observation Journal 
Day Two Text- Wednesday, February 25, 1998. 
Today we have seen no change in both plants A and B.   

In the picture above you can see one leaf from each plant, which was clipped on Monday prior to forming the hypothesis so each student could feel and closely observe a leaf from each plant.

Observation Journal 
Day Two Text Wednesday, February 25, 1998. 
Wednesday the children truly observed nothing different from Monday to Wednesday. 
 
 

 
 

Observation Journal 
Day  Three Text Friday, February 27, 1998. 
Plants A and B both appear to show little change. Both plants are still green and healthy looking. 
The leaves with vaseline appear to droop more than the others but that is the only noticeable change.  

Final Observation:  March 3, 1998 
By our final observation 3 leaves that had vaseline on the bottom had fallen off the plant and died. Only one leaf with vaseline on top died.  We believe that plants take in gases from the bottom, not top of each leaf.

Observation Journal  
Day Three Text- Friday, February 27, 1998. 
Friday: The students observed that the leaves with the Vaseline on the underside not only started to yellow, but they showed dry brown spots on top. Obviously the leaves were not going to live.

 

 

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What is Transpiration?