Objective

1. Objective • We will learn that all living things get their energy from the sun. We will learn the steps of photosynthesis by what reactants are used and which products are made.

2. PhotosynthesisCh. 8 Welcome to Unit 3

3. Living things need energy • Autotrophs: _______ and some prokaryotes are able to use the energy from the _______ to produce food. • Heterotrophs: __________, some prokaryotes, and most multicellular organisms _________ use the sun’s energy directly, therefore they need to consume ___________ as a food source.

4. ATP- Adenosine Tri-Phosphate • ATP is the ___________ molecule which plants and animals use for _________. • 3 Phosphates can be ___________ for energy. • ADP (adenosine di-phosphate) has with only ___ phosphates.

5. ATP and ADP are like battery strength Only 2 phosphate groups vs. all 3 means ______ power.

6. When does a cell need to use energy? • Active Transport: _____ cross cell membrane thru protein pump. • Sodium-Potassium ______ (3 Na+ out & 2 K+ in) • Synthesis of Nucleic Acids: DNA & RNA • Movement: • ATP needed for cell movement and __________. • ATP is actually only good for ________ term use, its poor at long-term storage of _______ amounts of energy. • Glucose is much better at long-term storage of _________. • Glucose stores ______more energy than ATP. • Cells keep a ______ supply of ATP; they ________ more from ADP when needed, by ___________________carbs like glucose.

7. Scientists who discovered Photosynthesis • Van Helmont (1643): Discovered that most of the ______ of a plant comes from ______. He weighed the plant and the soil. • Joseph Priestley (1771): Discovered a mint plant __________ a substance that kept a candle burning. Plants __________ oxygen. • Jan Ingenhousz (1779): Discovered that plants _______ produce oxygen in the presence of _________. • Melvin Calvin (1948): Determined the _________ of the Calvin Cycle.

8. Photosynthesis • Photosynthesis: is the process of _________ light energy into biochemical _________.

9. Where does photosynthesis occur? • Chloroplast: Organelle in plant cells only. • Chlorophyll: _________ that absorbs light. Appears _______ because it absorbs blue and red light. • Chlorophyll is just one pigment in plants, there are others colors: • Anthocyanin makes plants _____. • Carotenoids make plants look _________ or orange • As ___________ breaks down in the fall, we see these colors. Reflected Light Light Absorbed Light Transmitted Light

10. Reactants & Products • Reactants: CO2 + H2O (______________+ _________) • Along with light energy (for __________) • Products: C6H12O6 + O2(__________ + ___________) • Remember, CHO always make carbohydrates in _:_:_ ratio 

11. Photosynthesis = 2 Reactions • Both occurs in the _________. • Light Reactions: (Light ___________) AKA- Photophosphorylation • Takes place in two _______________. • Dark Reactions: (Light ______________) AKA- Calvin Cycle • Dark means __________ light needed, doesn’t necessarily happen only at night

12. Light Dependent • AKA- _________________________ • Photo= light, phospho= phosperous to make molecules, lation= process • Uses ________and _______ to make the energy storing molecules NADPH and ATP (which will be used in the dark reaction) and releases _________ as waste. • Takes place in the ____________ membrane (stacks).

13. Light Independent • AKA- ________________ • Uses ___________ of light reaction (NADPH and ATP) to ________ CO2 into C6H12O6 = _________ (sugar) • Takes place in the _________ (spaces)

14. Converting energy from electrons • The __________ point for photosynthesis • Take the energy from an ________election (photon of light) and use it to ________ H2O to makeNADPH. • Occurs by __________ the election from one thylakoid to another. • Stacks of thylakoids = ____________ • Chlorophyll pigments are found inside the thylakoid membranes (green)

15. Light Dependent Cycle • Photosystem II: Light is ____________ by chlorophyll, the energy from the light photons are ____________ to electrons, which then perform __________ to break water into ions (H+ and oxygen). • Photosystem I: Electrons and H+ are _____________ by NADP+ to makeNADPH. • Hydrogen Ion Movement: The inside of the thylakoid ___________ fills up with H+ ions, the makes the inside slightly _________, and the outside of the membrane slightly negative. • Electron Transport Chain: Electrons from photosystem II move to photosystem I, using their ________ to transport H+ from the stroma space to _________ the thylakoid membrane.

16. ATP Formation • The _______ phase of light reactions • ATP Synthase: a specialized ________ channel in the thylakoid membrane, located at the end of the ETC. • Converts ADP to ATP as H+ ions _______ through to the outside of the membrane. ATP synthase turns/spins like a _________ as ions pass through. • Chemiosmosis: occurs as H+ ions move across a ___________ to make ATP.

17. Calvin Cycle (light independent) • Uses ATP and NADPH made from photophosphorylation to _______ high-energy storage __________ (sugar- glucose). • Makes NADP+ and ADP (molecules ________ for light reactions).

18. Calvin Cycle Details • 6 molecules of CO2 enter the cycle from the ___________ (air). • They combine with 6 molecules containing 5 carbons each, this reactions forms 12 molecules with 3 carbons each. • ATP and NADPH are used to _________ the 3-carbon molecules into higher-_______ forms. • 2 of the 3-carbon molecules are used to make 6-carbon sugars such as _________. • 10 of the 3-carbon molecules remaining are ___________ into 5-carbon molecules, which will be used at the _________ again. • The Calvin Cycle uses 6 molecules of CO2 to make just __ molecule of 6-carbon glucose at the ____.

19. Reaction Formulas • Light Dependent Reactions in the _________ • NADP + H excited e- = NADPH • ADP + P ATP Synthase = ATP • Light Independent Reaction in the _______ • ATP + ______ + CO2 =C6H12O6 • Oxidation-Reduction Reactions always take place _______ • Oxidation: lose e- and H+, gain O2, _________ energy. • Reduction: lose O2, ______ e- and H+, take in energy.

20. Photosynthesis Formula • 6CO2 + 6H2O =C6H12O6 + 6O2 • Reactants: __ carbon dioxides + __ waters • Products: __ glucose + __ oxygens

21. Factors that affect photosynthesis • These can either slow down or speed up the process: • Light Intensity • More = _______ photosynthesis • Carbon Dioxide amount • More = ______ photosynthesis • Temperature • Too high or too low = _______ photosynthesis • High Heat: plants close their ______ (pores in leaves) to conserve _______. • Different plants have an ideal temperature range. • Trees that lose their leaves in the fall do _____ photosynthesize in the winter. • Type of plant: • C4 plants perform photosynthesis in different ________ of their leaves • CAM plants (_________) perform photosynthesis at _______

22. Plants produce oxygen • Most life on earth depends on ________ to live. • We breathe oxygen every day! • When plants split water during _____________, their leaves __________usable O2 in the air/water.