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Chapter 8 Photosynthesis

• 8.1 Photosynthesis uses light energy to make food

• 8. 4 Photosynthesis has a global impact

• Biology Honors only

• 8.2 The light reactions

• 8.3 The dark (Calvin cycle) reaction

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8.1 Describe the structure of a 8.1 Describe the structure of a chloroplastchloroplast

1. Photosynthesis takes place in the 1. Photosynthesis takes place in the chloroplastchloroplast

2. 2. ChlorophyllChlorophyll- chemical that make chloroplasts - chemical that make chloroplasts green in colorgreen in color

3. 3. Stroma-Stroma-

liquid in chloroplastliquid in chloroplast

4. 4. Grana are stacksGrana are stacks

Of thylokoid- checkOf thylokoid- check

notesnotes

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8.1 Formula for Photosynthesis8.1 Formula for Photosynthesis

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8.1 Steps of Photosynthesis8.1 Steps of Photosynthesis 1. 1. The The LightLight Reactions- Reactions- convert sunlight energy to chemical convert sunlight energy to chemical

energy- happens in energy- happens in thylakoidsthylakoids. Water . Water is is split split in this stepin this step

2. The 2. The DarkDark ( (Calvin CycleCalvin Cycle) reactions- ) reactions- makes sugar from carbon dioxide-makes sugar from carbon dioxide-

happens in the happens in the stromastroma

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8.4 Describe the carbon cycle8.4 Describe the carbon cycle

Some of the processes that occur on Some of the processes that occur on a global scale on Earth depend on a global scale on Earth depend on the metabolism of tiny chloroplasts the metabolism of tiny chloroplasts and mitochondria. and mitochondria.

An example is the An example is the carbon cyclecarbon cycle, the , the process by which carbon moves from process by which carbon moves from inorganic to organic compoundsinorganic to organic compounds and and back. back.

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8.4 Explain how photosynthesis is 8.4 Explain how photosynthesis is related to climate related to climate

Carbon dioxide in the atmosphere also Carbon dioxide in the atmosphere also traps heat from the sun that would traps heat from the sun that would otherwise escape from Earth back into otherwise escape from Earth back into space space

This important property, known as the This important property, known as the greenhouse effectgreenhouse effect, keeps the world climate , keeps the world climate warm enough for living things. warm enough for living things.

The greenhouse effect keeps the average The greenhouse effect keeps the average temperature on Earth some temperature on Earth some 10°C warmer10°C warmer than it would be otherwise than it would be otherwise

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See handouts

• Biology Honors only

• 8.2 The light reactions

• 8.3 The dark (Calvin cycle) reaction