Photosynthesis

Trapping the Sun’s Energy

Question: ■ How does a plant go from a tiny seed to a

redwood tree? Where does the mass come from?■ Write down, then share with your partner

What do you think?

What are the reactants in photosynthesis?

Water and carbon dioxide*and light, but this isn’t made of

atoms

What is the main product of photosynthesis?

GlucoseC6H12O6

Modeling photosynthesis activity

1. Read the list of materials2. Gather the list of materials3. Work through the procedure. Get approval and take a

picture before breaking apart your reactants4. Get approval and take a picture before breaking apart

your products

5. When approved with the products, you may dispose of the Marshmallows as you see fit

6. Complete the rest of the worksheet in a timely fashion.

Trapping Energy from Sunlight

■ Light energy is not always available, so energy must also be stored.

■ Photosynthesis – the process plants use to trap the sun’s energy and build glucose to store energy.

Light from the Sun

Where does photosynthesis take place?

■ Chloroplast contains stacks of thylakoids called grana.

■ Light-dependent reactions take place in the thylakoid membranes.

■ Light-independent (Calvin Cycle) reactions take place in the stroma

Two Cycles of Photosynthesis

Light-Dependent Reactions

■ Light is absorbed by chlorophyll■ Electrons are passed to NADPH which can add

them to the CO2 to make sugar■ This process also allows ATP to be made from

ADP and P which can provide energy for the Calvin Cycle

■ Water is split and replaces the lost electrons, releasing O2 gas

Calvin Cycle

■ CO2 + NADPH + ATP Glucose (sugar)

HW: Photosynthesis review worksheet side 1 only