1. Balancing Equations??? Not Again….. Writing Prompt ~ 03.11.2009 Look carefully at this equation. What does this equation relate to? Explain how you came up with your answer… CO 2 + H 2 O + light  Glucose + O 2 Reactants Products Balance the equation….. ____CO 2 + ____H 2 O + Light  1C 6 H 12 O 6 + ___O 2 Where does this reaction occur?

2. Photosynthesis It is the conversion of solar energy to chemical energy in a form that can be utilized by living organisms. 2 steps –Light reaction - Light Dependent reaction –Calvin cycle - Light Independent reaction occurs in the light as well as the dark

3. What’s the Ultimate energy source? The sun is ultimate energy source for virtually ALL life on earth. Plants and Cyanobacteria generate their own food by converting SOLAR energy to the stored energy of glucose (food & building materials). Plants and animals must then convert that food to an energy form useable at the cellular level.

4. Equation for Photosynthesis CO 2 + H 2 O + light -----> Glucose + O 2 Reactants Products Where does this reaction occur?

5. Where do these inputs come from? Energy (light) comes from the sun (or some other artificial light source. Water comes from the soil into the plant roots & through the plant to the leaves. Carbon Dioxide comes from the air and enters the leaves through stomata.

6. Light Dependent Reaction Light strikes chloroplasts of a leaf cell Energy from light energizes chlorophyll Energized chlorophyll splits a water molecule, giving off the oxygen as a gas (waste) and capturing the hydrogen atoms to use later. This is the place where you’ve learned that plants give off oxygen!!

7. Calvin Cycle (Light Independent Reaction) The fixation of carbon dioxide from atmosphere to make sugar (storing carbon to use for building / growing) Light is NOT necessary for this reaction- it takes place both during the day and at night Combines CO 2 with other carbon containing compounds form to sugar - Glucose (6 carbons) When you learned that plants take in CO 2 (carbon dioxide) this is where its used.

8. What kinds of light are involved?

9. Check it out…..