Photosynthesis NotesPhotosynthesis Notes

1)1) On your notes, define photosynthesis. On your notes, define photosynthesis. You can use your book!You can use your book!

2)2) Answer: Answer: PhotosynthesisPhotosynthesis is the process is the process by which a cell captures energy in by which a cell captures energy in sunlight and uses it to make food.sunlight and uses it to make food.

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Hand in Vocabulary SquaresHand in Vocabulary Squares Photosynthesis Notes #29Photosynthesis Notes #29 Photosynthesis video clipPhotosynthesis video clip P/R Compare/ContrastP/R Compare/Contrast Cell Processes WS Due MondayCell Processes WS Due Monday Lab days next week: Tuesday/ThursdayLab days next week: Tuesday/Thursday Cell Theory and Scientists QuizCell Theory and Scientists Quiz

During photosynthesis, plants and some During photosynthesis, plants and some other organisms use energy from the sun other organisms use energy from the sun to convert carbon dioxide and water into to convert carbon dioxide and water into oxygen and sugar.oxygen and sugar.

Photosynthesis takes place in two Photosynthesis takes place in two stages:stages:

1)1) Stage 1Stage 1 – Capturing the Sun’s Energy – Capturing the Sun’s Energy

Occurs in the leavesOccurs in the leaves Chlorophyll captures light energy and uses Chlorophyll captures light energy and uses

it to power the second stage of it to power the second stage of photosynthesisphotosynthesis

2)2) Stage 2Stage 2 – Using Energy to Make Food – Using Energy to Make Food

The cell uses the energy from Stage 1 to The cell uses the energy from Stage 1 to convert water and carbon dioxide into convert water and carbon dioxide into sugar and oxygen.sugar and oxygen. The water is absorbed by the rootsThe water is absorbed by the roots Carbon dioxide enters through openings on the Carbon dioxide enters through openings on the

bottom of the leaf called bottom of the leaf called stomatastomata..

Stage 2 continued…

The oxygen produced is given off as waste.The oxygen produced is given off as waste.

The sugars produced can be used in 3 ways:The sugars produced can be used in 3 ways:

1.1. As energy for the cell to carry-out its functionsAs energy for the cell to carry-out its functions

2.2. Used to make Used to make cellulosecellulose (the material that makes (the material that makes plant cell walls)plant cell walls)

3.3. Stored in the plant and consumed by animalsStored in the plant and consumed by animals

Photosynthesis Equation:

The process of photosynthesis is The process of photosynthesis is represented by the following equation:represented by the following equation:

Light EnergyLight Energy

6CO6CO22 + 6H + 6H22O O C C66HH1212OO66 + 6O + 6O22

carbon carbon waterwater sugarsugar oxygen oxygen

dioxidedioxide

(( = “yields”) = “yields”)

We write “light energy” and chlorophyll We write “light energy” and chlorophyll above the arrow because both are above the arrow because both are necessary for the chemical reaction to take necessary for the chemical reaction to take place.place.

Carbon dioxide and water are called Carbon dioxide and water are called raw raw materialsmaterials because these are what the plant because these are what the plant starts with.starts with.

Sugar and oxygen are called Sugar and oxygen are called productsproducts because these are what the plant makes.because these are what the plant makes.