Learning Objective

In this inquiry I will:

• make a leaf imprint that will help me find the pores, called stomata, that let gasses in/out of a leaf.

• review photosynthesis, and chloroplast structures.

• consider how stomata help the leaf maintain the homeostatic balance required for photosynthesis.

DOL

Today, I will write conclusions for the leaf imprint lab that earn 3 of 4 points on the lab report rubric.

Curiously Krulwich

A Blog by Robert Krulwich

"What a difference a leaf makes! Well, not one leaf. We have 3.1 trillion trees on our planet—that’s 422 trees per person. If we count all the leaves on all those trees and take a look at what they do collectively to the air around us, the effect—and I do not exaggerate—is stunning. I’ve got a video from NASA. When you see it, I think your jaw is going to drop—just a little." 

The Earth Has Lungs. Watch Them Breathe.

Follow the instructions I provided and prepare your leaf. Paint the top of one leaf, and the bottom of the other. We are only doing steps one and two for both leaves. It will need time to dry.  Here's a video to help.

We are going to use Cornell Notes formatting for our lab report. 

• You can look on the back of the instructions at the rubric so you will know what sections are included. 

• I encourage you to write notes in the margin that will help you organize your thoughts.

 Now, work with your partner to arrange the note cards on your table in the correct order. What do these chemical formula's represent?

Write the words for what each formula represents on the top of the cards.

What process is represented? 

Where does this take place in a plant?

Stoma (singular)/Stomata (plural): a structure on the surface of the leaf that regulates gas exchange. 

Here's a video from Carnegie Institution for Science explaining how plants "breathe".

But you can't see stomata with your naked eye, so it's necessary to make an imprint of the leaf. 

Where do you think you will find more stomata on the leaf? Top or bottom? Write a hypothesis.

Use the information we just covered to write an introduction for your lab. Pay attention to the three elements on the rubric. 

Look at your instruction sheet and write your "Methods" section. Use the rubric to help you.

Let's finish preparing the slides.

Why do you want five samples for top and bottom?

What goes in the "Data and Anaylysis" section of your report? 

• Create a table for your data. 
• Don't forget to label your drawing, and specify magnification.

Work with your partner to complete the investigation.  

So, let's review:

Today we learned that:

• gas exchange is necessary for photosynthesis to occur.
• stomata are the sites where gas exchange occur.
• most plants have _______ stomata on the underside of the leaf.