Essential Question: How do plants harness the suns energy?

The process of photosynthesis is a chemical reaction that converts light energy into chemical energy. Photo = light Synthesis = to make It is the most important chemical reaction on our planet.

Organisms that carry out photosynthesis are called producers or autotrophs - producers are the basis of all of Earth’s food chains

occurs in chloroplasts - the energy in the light is absorbed by the chlorophyll and converted to chemical energy

Plants Algae Some Bacteria Discuss question 6 with your partner then answer it.

Thylakoids found inside the chloroplast contain the pigment chlorophyll. thylakoids

Different wavelengths of visible light are seen by the human eye as different colors. WHY ARE PLANTS GREEN? Gamma rays X-raysUVInfrared Micro- waves Radio waves Visible light Wavelength (nm)

Why are plants green? Reflected light Transmitted light

Chloroplasts absorb light energy and convert it to chemical energy Light Reflected light Absorbed light Transmitted light Chloroplast THE COLOR OF LIGHT SEEN IS THE COLOR NOT ABSORBED

As the chlorophyll in leaves decays in the Fall, the green color fades and is replaced by the oranges and reds of carotenoids

- Grana- structures inside the chloroplast that are made of stacks of thylakoids. grana thylakoids

Stroma – the fluid filled space outside of the grana. stroma contains enzymes necessary to convert CO 2 into sugar which stores energy. stroma grana thylakoids

The Balanced Photosynthesis Equation CO 2 H2OH2OC 6 H 12 O 6 O2O2 Light

Reactants Products

stroma grana thylakoids Discuss with your partner… Where the chlorophyll is found Discuss with your partner… What we call stacks of thylakoids Discuss with your partner… What is the term used to describe the fluid filled space Discuss with your partner… Where in the chloroplast is light captured

Discuss and answer questions with your partner

How are the thylakoids, grana, and stroma related?

Bring In 1. light 2. Reactants CO 2 H 2 O Waste Product O 2 Makes and uses the product Sugar (glucose) 6CO 2 6H 2 O C 6 H 12 O 6 6O 2 light energy  +++

Two major parts Light Reactions Light Independent reactions (Calvin Cycle)

- capture energy in sunlight and transfer it to chemical energy - take place in thylakoid membrane of a chloroplast - Chlorophyll is found in the thylakoid disks and they absorbs energy from sunlight

Light reaction 1.Light is absorbed by chlorophyll in the thylakoid 2.enzymes split H 2 O and oxygen is released 3.energy from light is stored in ATP & NADPH

Discuss question 20 with your partners, then write your answer on your paper.

Discuss question 21 with your partners, then write your answer on your paper.

Two connected photosystems collect photons of light and transfer the energy to chlorophyll electrons The excited electrons are passed from the primary electron acceptor to the electron transport chains Their energy ends up in ATP and NADPH

The O 2 liberated by photosynthesis is made from the oxygen in water (H + and e - )

- energy is released when a phosphate group is removed - ADP is then produced (can be converted back to ATP) - Function: the chemical energy used for most cell processes

NADPH is formed (functions like ATP = energy) when electrons are added to NADP+ FUNCTION: the major electron carrier during photosynthesis

NADPH is an unstable molecule that stores chemical energy for the cell

The addition of a phosphate group to an organic molecule. Phosphorylation is important for many processes in living cells. ATP is formed during cell respiration from ADP by phosphorylation, in the mitochondria of eukaryotic cells and the chloroplasts of plant cells (photosynthetic phosphorylation).

1.Write the chemical equation for the light reaction. 2.Which products will be used in the next phase of photosynthesis? (page 226) 3.Why cant energy be stored as ATP and NADPH? 4.What is the second phase of photosynthesis? 5.What is another name for the second phase of photosynthesis?

1. Light reaction Light is absorbed by chlorophyll in the thylakoid - enzymes split H 2 O and oxygen is released - energy from light is stored in ATP & NADPH

Reactants Products Light + H 2 0 Occurs in the thylakoid membrane of the chloroplast O2 + ATP + NADPH 

Lets get started on our cellular energy foldable!

Cellular Energy Foldable: Chose one of the 4 tabs and write “Photosynthesis” below photosynthesis draw a picture of the organelle that conducts the process of photosynthesis.

Cellular Energy Foldable: Under the Photosynthesis tab, add the following information- 1.Chemical Equation for the light reaction (reactants products) 2. Steps of the light reaction 3.Picture of the light reaction (at least 4 colors)

Can occur during the light or the dark Discuss questions 29 with your partner then answer it.

The Calvin Cycle takes place in the stroma of the chloroplast Uses CO 2 from the atmosphere and energy from the light reactions stored in ATP & NADPH

The DARK Reactions = Calvin Cycle CO 2 from atmosphere is joined with the energy stored in ATP and NADPH to form glucose Glucose can be converted into other molecules like cellulose, which is used for structural support in plant cells.

Why store energy from the sun as sugar and not ATP? - ATP is an unstable compound – it doesn’t last a long time. - sugar (glucose) is stable and can store the energy for a long period of time. - sugar can be used to build even larger storage molecules (polysaccharides)

A Photosynthesis Road Map Chloroplast Light Stack of thylakoids ADP + P NADP  Stroma Light reactions Calvin cycle Sugar used for  Cellular respiration  Cellulose  Starch  Other organic compounds

1.Light reaction (depends on light) Captures sunlight Breaks down water molecules to produce electrons to form ATP and NADPH Produces oxygen as a waste product 2.Calvin Cycle (does not directly depend on light) Uses ATP, NADPH (from light reaction), and CO 2 to make glucose Glucose is the product in the Calvin cycle

It's not that easy bein' green… but it is essential for life on earth!

Glue the photosynthesis concept map onto page 64 of your notebook

Photosynthesis Light-Dependent Reactions Water & Energy from Sunlight Thylakoid Membranes ATPNADPH Oxygen Chloroplast Stroma Calvin Cycle ATP NADPH Glucose (High Energy Sugars) Includes Use Takes place in To Produce Takes Place in Of Uses To Produce Carbon Dioxide

Cellular Energy Foldable: Chose one tab next to photosynthesis and write the overall balanced equation of photosynthesis.

Cellular Energy Foldable: Under the overall equation tab, add the following information- 1.Chemical Equation for the dark reaction (reactants products) 2. summarize the dark reaction 3.Picture of the dark reaction (at least 4 colors)