1. CATALYST
How do plants get
energy?
2. How do animals get energy ?

2. Essential Question
2.WHY DO LEAVES Why do leaves chang change color in the f fall?

3. Objectives: I CAN…
□Relate the structure of a chloroplast to the events in photosynthesis

4. PHOTOSYNTHESIS

5. Topic: Photosynthesis
Take Notes!
Topic: Photosynthesis
Photosynthesis
Process that uses the sun’s energy to make simple sugars

6. This diagram shows how the energy from the sun goes into the plant
This diagram shows how the energy from the sun goes into the plant. The plant uses this energy to produce glucose and oxygen. Carbon dioxide comes back to the plant as well as water.

7. The general equation for photosynthesis is written as:
6CO2 + 6H2O→C6H12O6 + 6O2
Carbon Dioxide + Water Glucose + Oxygen

8. Topic: Photosynthesis
Take Notes!
Topic: Photosynthesis
Photosynthesis Equation
6CO2 + 6H2O→C6H12O6 + 6O2

9. Read:
The chloroplast is the part of the plant’s leaf where photosynthesis takes place. The chloroplast contains pigments, which are molecules that take in specific wavelengths of sunlight. Wavelengths of sunlight transfer energy. The most common pigment in the chloroplast is chlorophyll. Chlorophyll is a plant pigment that absorbs most wavelengths of sunlight except green. Because it cannot take in the green wavelength, it reflects the green. This is what makes leaves look green. In the fall, leaves stop producing chlorophyll, so other pigments become visible. This gives leaves a wide variety of colors.
Read out loud with your table. Answer the questions.

10. Chloroplast in plant cells
Where does photosynthesis take place?
Chloroplast in plant cells
2. What is the purpose of pigment?
Molecules that take in specific wavelengths of sunlight
3. What is the most common pigment in plants?
Chlorophyll
4. Why do leaves change color in the fall?
Plants stop producing chlorophyll so other pigments become visible
Lets go over the answers.

11. Here is a diagram of a plant cell. Can you find the chloroplasts?

13. To trap the energy in the sun’s light, the thylakoid membranes contain pigments, molecules that absorb specific wavelengths of sunlight.

14. Chloroplasts contain several kinds of pigments, the most common is chlorophyll.

15. Topic: Photosynthesis
Take Notes!
Topic: Photosynthesis
Pigments
molecules that absorb specific wavelengths of sunlight
Chlorophyll most common in leaves

16. WHY ARE PLANTS GREEN?
Chlorophyll absorbs most wavelengths of light except green. Chlorophyll reflects the green, so that’s what you see!

17. Topic: Photosynthesis
Take Notes!
Topic: Photosynthesis
The light-dependent reactions convert light energy into chemical energy (ATP)
ATP fuels the light-independent reactions that produce simple sugars.
Two STAGES of Photosynthesis

19. 2. Looking at the table, what months will all of the leaves be green?
The following table shows how much of each pigment is present within a leaf during different months. Use the information to answer the questions that follow.
Pigment
May
June
July
August
September
October
Chlorophyll
2.92
2.95
3.37
3.15
1.58
0.6
Xanthophyll
1.12
1.05
0.89
0.82
1.17
1.32
Carotene
2.32
2.25
2.22
2.20
2.62
2.88
1. During which months is the amount of Carotene in a leaf greater than the amount of Chlorophyll?
2. Looking at the table, what months will all of the leaves be green?
Lets answer these together.

20. So lets review

21. WHY DO LEAVES CHANGE COLOR IN THE FALL?