LESSON PLAN

Name(s): Julia Neumann

Title of Lesson: Photosynthesis

Date of Lesson: 12/2/03

Length of Lesson: 50 minutes

Description of the Class:

Name: Biology

Source of the Lesson:

Biology with Computers, Experiment 31B

TEKS Addressed:

Include TEKS that are content specific as well as TEKS that are process skills.

(4) Scientific processes. The student knows how to use tools and methods to conduct science inquiry. The student is expected to:

(A) Collect, analyze, and record information to explain a phenomenon using tools including beakers, Petri dishes, meter sticks, graduated cylinders, weather instruments, hot plates, dissecting equipment, test tubes, safety goggles, spring scales, balances, microscopes, telescopes, thermometers, calculators, field equipment, computers, computer probes, timing devices, magnets, and compasses; and

(B) Collect and analyze information to recognize patterns such as rates of change.

(8) Science concepts. The student knows that complex interactions occur between matter and energy. The student is expected to:

(B) Identify that radiant energy from the Sun is transferred into chemical energy through the process of photosynthesis.

I. Overview

Students will use the computers and CO2 probes to observe what happens to the carbon dioxide level when photosynthesis is occurring in Spinach leaves.

II. Performance Objectives

The student will be able to:

-Define photosynthesis and relate its significance to life on earth.

-Write the overall equation for photosynthesis.

-Relate that plants get their energy from the sun to produce food.

-Predict the relationship between light and CO2 level.

III. Resources, Materials, and Supplies Needed

 (7) Computers, (7) CO2 probes, (7) Vernier Interfaces, Spinach leaves, Plant to show class and special leaves (ie Coleus), (7) Lamps

IV. Safety Considerations

Students must carefully handle equipment and take care when moving the lamp to avoid burns.

V. Supplementary Materials, Handouts

Pre/Post assessment, data collection sheet

Five E Organization

Teacher Does Student Does

Engage: Have students explain what they think gives plants energy. Ask how plants store this energy. Write their ideas on the board and leave them up there for the discussion after the lab. Questions: How do humans get energy? What about plants, how do they get their energy? Where do they store it? Where does wood come from?

Hoped for student response: Students are attentive and willing to discuss. Students will know plants get energy from sunlight. Expected student responses: Humans get their energy from food, while plants get their energy from the sun. Plants use nutrients in the soil to make wood.

 Give students pre-assessment

Evaluate: Are students engaged? Did students complete their pre-assessment?

Explore: Students will use the CO2 probes to determine the level of CO2 in the chamber in light and dark conditions. For the light condition, students will place a given amount of Spinach into the chamber and will record data for 10 minutes, watching the graph on the computer carefully. They will sketch their graphs on a separate sheet of paper, taking them from the computer screen. Before lab, students will be asked to predict the results before taking data. Questions: When a graph is increasing, what does it look like? What about decreasing? What does this graph look like? Is it increasing or decreasing? What does this mean? How can you have a negative amount of CO2? What does it mean if the CO2 level increases?

Hoped for student response: Students conduct the experiment and follow directions closely. Expected student responses: A graph that is increasing looks like this, while one that is decreasing looks like this (students show a sketch). This one is decreasing because the plant is using CO2. If it is positive, then it must be giving off CO2.

Evaluate: Are students on-task? Are they understanding the measurements they are taking and what they mean? Monitor student groups and ask questions to make sure they understand.

Explain: Learning Experience(s): Students will discuss the results of the experiment. Questions: Will ___ come show me a sketch of what the graph looked like? What happens when plants get sunlight? Do they get sunlight every hour every day? Why not? What do they do at night? How does this relate to plant growth? Plants get the energy they need to make their own food from a process called photosynthesis, whereby they use CO2, water and sunlight and end up with oxygen and sugar. How does this explain your results?

Hoped for student response: Students will look at their data and report their findings. Expected student responses: The plant had a negative rate of CO2, meaning it decreased. It means that the plant was using the CO2. This must mean that the plant uses CO2 when it is getting light from the sun.

Evaluate: Monitor caliber of student responses and determine whether more time is needed to explain the topic to ensure they “get it”.

Extend/Elaborate: Learning Experience(s): Students will discuss their initial ideas of how plants make sugar and contrast them to their new ideas.  Questions: Now that we’ve done our lab, how do you think plants get their energy to make food? How does that compare to your initial ideas?

Hoped for student response: Students participate in the discussion. Expected student responses: We were wrong. Plants get their energy to make food (sugar) to grow from the sun, not the soil.

Evaluate: Can students replace their old ideas with new ones? Are students paying attention and participating?

Name:_______________________________

Photosynthesis Lab

Check each box as you complete the corresponding step.

q Turn the lamp on.

q Place a given amount of spinach into the chamber and close the chamber (see diagram above).

q Verify with one of the instructors that your lab is set up correctly BEFORE YOU BEGIN COLLECTING DATA.

q Click the “Collect” button to begin data collection of the reaction.

q Observe the graph on the computer as it collects data. Sketch this graph on your collection sheet. While the data is collecting, record the carbon dioxide level every thirty seconds in your data table.

q After ten minutes, stop data collection.

q Raise your hand for an instructor to check your data and give you permission to return to your seats.

Warm-up

Choose the best answer:

1) What is the main mechanism that allows plants to get energy to grow?

a) nutrients in the soil go up through the roots and give plants energy to grow

b) plants capture energy from the sun and use carbon dioxide from the air to make sugar, which gives them energy to grow

c) plants get energy from fertilizer

2) What occurs during photosynthesis?

a) Carbon dioxide and water, in the presence of sunlight, are made into sugar and oxygen

b) The plant absorbs sugar and other nutrients from the soil

c) The leaves of a plant give off carbon dioxide

3) During photosynthesis, plants use ___________ from the air and H20 to produce __________ and _________.

What I Have Learned

1) What do plants use during photosynthesis? How does the experiment show this? (you can use graphs, pictures or anything you think would be appropriate to answer this question)

2) How do plants get energy to make their food?

3) What do plants make during photosynthesis?

Data Collection:

Time (minutes)	Carbon dioxide level (parts per thousand, ppt)
0
.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
8.5
9
9.5
10

Sketch of graph: