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Chapter 2 : Lesson 1 Photosynthesis
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PHOTOSYNTHESIS How Do Living Things Get Energy From the Sun?
Read pg. 45 and talk about Figure 1
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The Sun as an Energy Source
Photosynthesis – the process by which a cell captures energy in sunlight and uses it to make food The food is called glucose
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The Sun as an Energy Source
Nearly all living things obtain energy either directly or indirectly from the energy of sunlight that is captured during photosynthesis
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Producers and Consumers
Producers make their own food – also known as autotrophs Consumers don’t make their own food – also known as heterotrophs Many heterotrophs get food from eating other organisms
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What Happens During Photosynthesis?
During photosynthesis, plants and some other organisms absorb energy from the sun and use the energy to convert carbon dioxide and water into sugars and oxygen
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Takes place in two stages: 1. Plants capture sun’s energy
What Happens During Photosynthesis? Takes place in two stages: 1. Plants capture sun’s energy 2. plants produce sugars More detail about both stages on next slide…
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What Happens During Photosynthesis?
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Chlorophyll – the main pigment for photosynthesis
Stage 1: Capturing the Sun’s Energy Chlorophyll – the main pigment for photosynthesis 1. Plants capture sun’s energy 2. plants produce sugars More detail about both stages on next slide…
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Chlorophyll – the main pigment for photosynthesis
Stage 1: Capturing the Sun’s Energy Chlorophyll – the main pigment for photosynthesis 1. Chlorophyll captures energy from sunlight a. Happens mostly in leaves
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b. Water in the chloroplasts is split into hydrogen and oxygen.
Stage 1: Capturing the Sun’s Energy b. Water in the chloroplasts is split into hydrogen and oxygen. c. Oxygen is given off as a waste product d. The hydrogen is used in stage 2
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Stage 1: First Stage of Photosynthesis The first stage of photosynthesis powers the “energy engine” of the living world.
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Stage 1: Virtual Lab???
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Stage 1: Plants capture sun’s energy Stage 2: plants produce sugars
Remember…2 stages of photosynthesis Stage 1: Plants capture sun’s energy Stage 2: plants produce sugars
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Photosynthesis What is the process of photosynthesis?
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Photosynthesis What is the process of photosynthesis? Light energy is changed to cell energy Sugars are produced
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Cells produce sugars in stage 2 The sugar is glucose – C6H12O6
Stage 2: Using Energy to Make Food Cells produce sugars in stage 2 The sugar is glucose – C6H12O6 Water and carbon dioxide combine chemically to form sugars – oxygen is released
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Producing Food The second stage of photosynthesis makes food for a plant. How can the information for Stage 1 and Stage 2 be completed?
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Producing Food The second stage of photosynthesis makes food for a plant. How can the information for Stage 1 and Stage 2 be completed? chlorophyll sunlight energy Carbon dioxide sugars
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The Photosynthesis Equation
Light Energy L 6O2 Light Energy Light Raw materials - materials needed for the chemical reaction to occur – (the molecules on left side of equation) – light energy is not a raw material, but written on the left to show it’s used in the reaction 6 molecules of carbon dioxide and 6 molecules of water
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The Photosynthesis Equation
Light Energy Light Energy 6O2 L Light Products – compounds that were chemically combined after the reaction – (the molecules on right side of equation) 1 molecule of glucose and 6 molecules of oxygen
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Circle two products of photosynthesis? Glucose c. Carbon dioxide
Assess Your Understanding Circle two products of photosynthesis? Glucose c. Carbon dioxide Oxygen d. Chlorophyll
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2a. Circle two products of photosynthesis? Glucose c. Carbon dioxide
Assess Your Understanding 2a. Circle two products of photosynthesis? Glucose c. Carbon dioxide Oxygen d. Chlorophyll
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Assess Your Understanding
2b. Refer to figure 3 on pg Where does the hydrogen that is used in Stage 2 of photosynthesis come from?
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Assess Your Understanding
2b. Refer to figure 3 on pg Where does the hydrogen that is used in Stage 2 of photosynthesis come from? Hydrogen comes from water that is split apart in Stage 1.
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Assess Your Understanding
c. Would you expect a plant to produce more oxygen on a sunny day or a cloudy day? Explain. vs.
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Assess Your Understanding
c. Would you expect a plant to produce more oxygen on a sunny day or a cloudy day? Explain. vs. On a sunny day; more sunlight would be available for photosynthesis
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I get it! Now I know that during photosynthesis…
Assess Your Understanding I get it! Now I know that during photosynthesis…
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I get it! Now I know that during photosynthesis…
Assess Your Understanding I get it! Now I know that during photosynthesis… Plants absorb energy from the sun and produce sugar (food) and oxygen.
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What are the two raw materials of photosynthesis?
One more to check What are the two raw materials of photosynthesis? Glucose c. Carbon dioxide Water d. Oxygen
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What are the two raw materials of photosynthesis?
One more to check What are the two raw materials of photosynthesis? Glucose c. Carbon dioxide Water d. Oxygen
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