CI /MSMM 5E Lesson Plan Template

Title of Lesson: What’s in a Leaf and what does it do?

UFTeach Students’ Names: Mackenzie Peil and Dianet Falcon

Teaching Date and Time: December 3, 2014; 12:50-2:40

Length of Lesson: 50 minutes

Course / Grade / Topic: Pre-Aice Biology, 9th grade, Cell Structure and Photosynthesis

Source of the Lesson:

●Mary Jones and Geoff Jones IGSE Cambridge Biology Coursebook (Second Edition)

Embedding Strategies Based on Field Interactions, Making Thinking Visible and CTS:

I am including the following teaching strategies with these students because…

Recommended strategy based on field interactions / Justification for selecting this strategy
Based on field interactions, students work best when they can interact with each other and the teacher, and discuss ideas as they learn. / In class, students are used to learning by having class discussions, and answering questions presented by the teacher.
Recommended strategy based on MTV routines / Justification for selecting this strategy
Based on MTV, the Claim-Support-Question will be useful in our class. / We want students to be able to think thoroughly about their ideas. This will delineate any misconceptions so that they can be clarified.
Recommended strategy based on CTS / Justification for selecting this strategy
Use hands-on activities and visual aids so that students can see the anatomical parts of the plants and understand their function. / It can be difficult to learn plant anatomy without seeing the parts of the plant and how they work with each other.

Florida Standards(MAFS, NGSSS, LAFS):

MAFS, NGSSS, LAFS with Cognitive Complexity:

Standard Number / Benchmark Description / Cognitive Complexity
SC.912.L.14.7 / Relate the structure of each of the major plant organs and tissues to physiological processes. / 2

Concept Development:

Performance Objectives

Students will be able to:

  • Assess the functions of plant tissues and organs and how they relate to photosynthesis
  • Describe the significance of the distribution of chloroplasts, stomata and mesophyll, and vascular bundles in terms of function in relation to photosynthesis
  • Thoroughly explain how plants get Carbon Dioxide and Water
  • Label the structure of a cross section of a leaf

Materials List

●34 microscopes

●51 Exploration Worksheets

●51 Assessment Worksheets

●51 Romaine Lettuce Leaves (1 per student)

●34 Scissors

●75 Microscope Slides

●75 slide covers

●34 pipettes

●34 trays/little baskets (something to put materials for each group in)

●34 50 mL beakers (or the smallest beakers you have)

●Roll of paper towels

Advance Preparations

●Print out Exploration and Assessment worksheets

●Create and set up powerpoint with projector

●Microscopes will be set up on the lab tables around the classroom

●Groups will be assigned based on who they share a table with

●Put a leaf, pipette, 2 slides, and 2 slide covers in each tray/basket

Safety

  • The students will not be required to wear goggles during this exploration. However, the students will be handling slides and coverslips which are easily broken. If a student breaks the glass, they are to alert one of the teachers in the classroom and it will be carefully cleaned up. Students are not to try to clean it up by themselves. Students will not be carrying microscopes around the classroom as they will be set up on the lab tables around the room prior to class starting. Since each student will have their own microscope, each student will have to know the proper way to use a microscope and will be told that the light base on the scope gets hot over the course of the class period so they need to be careful as to not touch it.

5E Lesson:

Engagement / Time: 15 minutes
What the Teacher Will Do / What the Teacher Will Say
Probing/Pressing Questions / Student Responses (correct responses)
Possible Misconceptions
Introduce ourselves and the lesson.
Slide 1 / My name is Ms. Falcon/Ms. Peil and today we’re going to talk about plant structures and how they relate to photosynthesis.
Introduce the Venus Flytrap video. / We’re going to start off watching this video on Venus Flytraps.
Play Video
Slide 2 /
  • 16:36

Ask the students about Venus Flytraps. / What kind of behavior did you all notice about Venus Flytraps and pitcher plants? / They eat flies
[They attract bugs with their nectar and trap them]
Clarify a common misconception. / What kind of animals does these plants consume? / flies and mosquitoes
[Any type of animal small enough to fit in the trap]
Ask the students why this plant would exhibit this behavior. / Why would a plants like the Venus Flytrap and pitcher plant eat insects? / Because they have the ability to do so.
[The plant was not able to get a sufficient amount of nutrients from the soil, so it developed an adaptation in order to obtain the necessary nutrients]
Relate to today’s lesson.
Slide 3 / Most of the time when we think of plant structures, we are mostly considering leaves for photosynthesis, flowers for reproduction, roots for transport of water and nutrients. We wanted you to take this chance to see that plants are amazingly diverse and there are many amazing adaptations they have to survive in often harsh environments.
Slide 4
Get the students talking about what they already know of plant structure and function. [DF1] / Let’s take a look at a cross section of a leaf! We are going to go through all of these structures together and figure out what each of them is and then talk about their functions. The first structure is A. It is on both the top and bottom of the leaf. Which structure do you think this is? / Epidermis
[Cuticle]
What do you think the cuticle is made of?
Have you ever noticed that some leaves are shiny?
What do you think is the purpose of a waxy cuticle covering the outside of the leaf?
Structure B points to that blue layer at the top of the leaf. Which structure do you think this is? / Cuticle
[Epidermis]
What is the purpose of this covering layer of cells?
Did you know you skin is also called your “epidermis”?
Structure C is very important for photosynthesis. They are a lot lined up and packed close together. What are these? / Spongy mesophyll
[Palisade Mesophyll]
What does the color tell you about the function of this layer of the leaf?
Why do you suppose it is right beneath the epidermis?
Bundle Sheath Cells / Structure D is pointing at the red circular formation of cells surrounding E and F. Does anyone have an idea of what this would be? / I have no idea
[Bundle Sheath cells]
Just by looking at this diagram, whatdo you suppose the job of these cells are? / [Protect and surround the xylem and phloem]
Structure E is pointing to the top set of small tubes. Who can tell me what this is? / Phloem
[Xylem]
What is the job of the xylem in the plant? / [Transport water from the roots to the rest of the plant]
Structure F is pointing to the bottom set of small tubes, which is below the xylem. What is this structure? / Xylem
[Phloem]
Who can tell me what the function of the phloem is? / [Transport sugars made in photosynthesis to the rest of the plant]
Why do you think that the xylem and phloem are so close to each other?
Why is their location in in the leaf in relation to the mesophyll layer important to the plant for photosynthesis? / [Located close to the mesophyll to allow for the quick transfer of reactants and products to the mesophyll for photosynthesis]
Structure G is similar to the layer on the top of the leaf except it has structures I and J embedded in it. Who has an idea what this structure is? / [Lower Epidermis]
Structure H is more spaced out to allow for air spaces in the leaf. What is this structure? / [Spongy Mesophyll]
How does the spongy layer differ from the palisade mesophyll in how they look? / [Palisade layer is more organized and the spongy cells have large spaces between them]
Based on those observations, what do you think the function is? / [Stores CO2 which is then used for photosynthesis after entering through the stomata and O2, which is product of photosynthesis, before being let out of the cell or used for cellular respiration]
Structure I is pointing to the cells around the opening in the lower epidermis. What is the name of these cells? / [Guard Cells]
Structure J is important to leaf function. It is the hole in the bottom of the leaf that opens and closes and is controlled by the guard cells. What is this structure? / [Stoma]
Based on the shape of the cell ho can tell me what the purpose of the stoma in the lower epidermis is? / The stomata is responsible for gas exchange. Air from the atmosphere enters the leaf through the stomata to enter the air spaces in the spongy mesophyll layer before being used for photosynthesis.
Structure K is made up of the xylem, phloem, and bundle sheath cells. Structure K is known as what? / Stoma
[Vein]
Is the vein visible by the human eye? / No
[Yes]
Exploration / Time: 15 minutes
What the Teacher Will Do / What the Teacher Will Say
Probing/Pressing Questions / Student Responses (correct responses)
Possible Misconceptions
Introduce the lab that they will be doing / Today we are going to be working in pairs using microscopes to look at leaves. For each group, you will create 2 wet slides. One person will make the first slide will have the top of the leaf facing up. Theother person will make the second slide and will have the bottom of leaf facing upwards.[DF2][DF3]
Make sure all students know how to create a wet slide.
Slide 6 / Let’s take a look at how to make a wet mount slide. The first step is to take a microscope slide and using the pipette, add a drop of water to the middle of the slide. Using the scissors,cut a small piece of your leaf close to eh middle and place it in the water on the slide[DF4]. Carefully place the coverslip over the leaf and water drop and make sure there isn’t an air bubble. Now it is good to go! / Note: Students will have questions about how thick their sample should be, and will need help before they can move on. [DF5]
Go over how to use a microscope
Slide 8 / I just want to do a quick review on how to use a microscope. There are two different focuses. The large knob is the course focus, which you use on the smallest magnification (4x) only. The small knob is fine focus. You use this focus on 10x and 20x lenses.
  • Begin by placing your slide under the 4x lens. What magnification are you seeing? Remember to multiply your lens by the 10x eyepiece which would equal 40 times magnified
  • Use the coarse focus to get as clear an image as possible, then use the fine focus to sharpen your view
  • Then move the 10x lens into place. What is the magnification now? 10x equals 100 times magnified
  • Using only the fine focus, get your lettuce leaf into focus if you have a problem, go back to the 4X and try again.
  • Once you have it focused on the 10X, you can then move the 40X lens into place. What do you see?
  • If you are really good at this and your neighbor is struggling, then help them out!

Go over safety
Slide 9 / For safety measures for this experiment, you do not have to wear goggles, but please do be careful with the pipettes and scissors.You will also be handling glass today; the microscope slides and cover slides are extremely fragile and can break very easily. You need to be extremely careful when handling the slides and covers. If you happen to break one of them, please let one of us know and we will take care of it.
TCirculate the room and ask students about what they see. / What do you expect to see?
Help students connect the diagram on the board to what they are looking at in their microscopes.[DF6] / [Top of the leaf: Chloroplasts]
[Bottom of the leaf: Stomata]
Explanation / Time: 10 minutes
What the Teacher Will Do / What the Teacher Will Say
Probing/Pressing Questions / Student Responses (correct responses)
Possible Misconceptions
Go over what the students put for the predict questions
Slide 10 / Before we go into what you all saw through the microscope, lets first go through the predict questions. What is the advantage of leaves having a large surface area? / [To expose as large an area as possible to sunlight]
Being thin? / [To allow sunlight to penetrate to all cells, to allow CO2 to diffuse in and O2 to diffuse out as quickly as possible]
What did you expect to see when you looked at the top/bottom of the leaf? Were there any surprises? / Answers may vary
Go over what they saw and comprehension questions
Slide 11 / What did you see in the top of the leaf? / Answers will vary
Cell walls, chloroplasts, many cells, palisade mesophyll
Did you see masses of green dots? What do you suppose they were? Was the top view noticeably different? What was different? Why do you suppose that there were more chloroplasts at the top at the leaf? / [Chloroplasts]
What did you see in the bottom of the leaf? / Answers will vary
Why do you think the palisade mesophyll cells were so tightly packed together? / [More cells can fit and undergo photosynthesis, sunlight has less distance to travel, no wasted space]
How does this help with/affect photosynthesis? / [Increases the amount of products since more cells will undergo synthesis at a time]
Talk about the top 3 main concepts in relation to photosynthesis
Slide 12 / We are going to expand on some structures and their significance to photosynthesis. The first topic is the chloroplasts. What do you the significance of the distribution of chloroplasts is in relation to photosynthesis? / [Arranged to obtain the most sunlight possible, contain chlorophyll, located mainly in palisade mesophyll cells]
The second topic is stomata and mesophyll. How are these two structures related and what is their significance in relation to photosynthesis? / [Gas exchange; guard cells open stomata to let air into/out of the air spaces in spongy mesophyll; once in the leaf, air diffuses in and out of cells (mesophyll) through the cell wall and cell membrane]
Slide 13 / The third topic is concerning the vascular bundle, which is also known as the vein. What is the significance of the vein in relation to photosynthesis? / [Xylem has thick walls and transports water to the leaf, some of which is used in photosynthesis; phloem has thin walls and transports sucrose and other substances away from the leaves throughout the plant; the xylem and phloem also provide structural support to the plant]
Elaboration / Time: 5 minutes
What the Teacher Will Do / What the Teacher Will Say
Probing/Pressing Questions / Student Responses (correct responses)
Possible Misconceptions
Introduce the next activity/discussion that will be done in class / Now that we have a basic understanding of leaf structure, let’s go back to how this whole lesson started. Plants have different adaptations in order to survive and thrive in their environments. An example of this would be the venus fly traps we talked about in the beginning of class. They have adapted to acquire nutrients from catching animals in their trap since their soil lacks the nutrients that the plant needs to survive. We are going to look at cross sections of plants that belong to different environments.
Here is our first leaf. What can you see is different in this leaf than the general structure we were looking at earlier? / [Big space/stoma closer to the middle of the leaf]
Does anyone see any structures that have changed in order to adapt to this environment? / [The epidermis is much thicker than in other leaves]
Can anyone guess what environment this leaf is from based on the adaptations inside the leaf? / Grassland
[Desert]
Does someone have an idea what plant this is from? / I don’t know
[Cactus]
This is a Cactus Leaf. You can see by the change in location of the stoma and the thicker epidermis layers that this leaf is from a hot, dry environment.
Here is our next leaf structure. Who can tell me what they see is different in this leaf from the general idea of a leaf from earlier? / [Bigger spongy mesophyll area of leaf, larger air sacs]
What do you think the purpose of having larger air sacs is? What is the advantage of this adaptation? / [store more air, help the leaf float]
Based on the structure, what type of environment do you think this leaf is from? / [Aquatic environment]
This is an aquatic plant leaf! The large air sacs don’t only allow for the leaf to hold more CO2 and O2, but this also allows for the leaves to float in water, such as lily pads.
This is our last leaf structure. Who can tell me what they see is different in this leaf from previous leaves? / [Vein is bigger, leaf is thinner]
What structure is more noticeable in this leaf structure than others? Why do you think this structure is so important to this plant? / [Vein, xylem and phloem]
[The leaves need more water at a higher rate]
What environment do you think this leaf is from? / Desert
[Grassland]
It is from the grassland! Plants here have developed the adaptation to grow quickly only when an adequate amount of water is available.
Evaluation / Time: 5 minutes
What the Teacher Will Do / What the Teacher Will Say
Probing/Pressing Questions / Student Responses (correct responses)
Possible Misconceptions
Ask the students to complete their worksheets. / Okay everyone, go ahead and finish your worksheets. When you’re done, pass them all the way to your left.

What’s in there and what does it do?