Chemical Energy, ATP, & Photosynthesis Chapter 4 Sections 4.1, 4.2, and 4.3

4.1 How do living things get ATP? ATP is the energy carrier in living things – it is usable energy for the cell (chemical potential energy). ATP is the energy carrier in living things – it is usable energy for the cell (chemical potential energy). ATP stands for Adenosine triphosphate. ATP stands for Adenosine triphosphate. Living things get ATP from breaking down carbon based molecules. (carbohydrates & lipids) Living things get ATP from breaking down carbon based molecules. (carbohydrates & lipids) Starch molecule Glucose molecule

This is how it works phosphate removed

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4.2 & 4.3 Photosynthesis The process of photosynthesis captures energy from sunlight and converts it into sugar (glucose - CPE). The process of photosynthesis captures energy from sunlight and converts it into sugar (glucose - CPE). This process happens in organisms called autotrophs or producers. (Need to make their own food) This process happens in organisms called autotrophs or producers. (Need to make their own food) This process takes place in and organelle called the chloroplast. This process takes place in and organelle called the chloroplast. The chloroplast has a green pigment in it called chlorophyll that is responsible for capturing the light energy. The chloroplast has a green pigment in it called chlorophyll that is responsible for capturing the light energy.

Let’s label the inside of a chloroplast C 6 H 12 O 6 (glucose) Contains: chlorophyll 4. thylakoid sunlight 1 six-carbon sugar 3. 6H 2 O 7. 6CO 2 from the atmosphere 5. 6O 2 chloroplast Energy carrying molecules are being transferred to light independent reactions stroma ( fluid outside the thylakoids ) 8. Light independent reaction 1.

So how does photosynthesis work? The first stage of photosynthesis is called the Light Dependent Stage. Purpose: To capture and transfer energy. First, light is captured by the chlorophyll in the thylakoid. First, light is captured by the chlorophyll in the thylakoid. Thylakoids: membrane enclosed compartments; membrane contains chlorophyll & other light- absorbing molecules. Thylakoids: membrane enclosed compartments; membrane contains chlorophyll & other light- absorbing molecules. Grana: stacks of thylakoids Grana: stacks of thylakoids

The Light Dependent Stage Second, the energy is transferred along the thylakoid membrane and water is broken down. Oxygen molecules get released at this point. Second, the energy is transferred along the thylakoid membrane and water is broken down. Oxygen molecules get released at this point. Third, energy is then transferred to ATP to be used for the second stage of photosynthesis. Third, energy is then transferred to ATP to be used for the second stage of photosynthesis.

So how does photosynthesis work? The second stage of photosynthesis is called the Light Independent Stage/ Calvin Cycle/ Dark Cycle. This process takes place in the stroma. This process takes place in the stroma. Stroma: The fluid outside of the thylakoids. Stroma: The fluid outside of the thylakoids. First, carbon dioxide is added from the atmosphere to help in the chemical reactions. First, carbon dioxide is added from the atmosphere to help in the chemical reactions. Second, a molecule of a simple sugar (glucose) is formed. This molecule stores some of the energy captured from the sun. Second, a molecule of a simple sugar (glucose) is formed. This molecule stores some of the energy captured from the sun.

The chemical formula for photosynthesis 6CO 2 + 6H 2 O + light C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + light C 6 H 12 O 6 + 6O 2 (reactants) (products ) (reactants) (products ) Carbon dioxide plus water plus light yieldsGlucose and oxygen

What kind of energy transformation takes place in photosynthesis? Radiant (light)  Chemical (with a loss of heat of course!) Radiant (light)  Chemical (with a loss of heat of course!)

Chemosynthesis Some organisms still make their own food, but they do not use light - they use chemicals. Some organisms still make their own food, but they do not use light - they use chemicals. Chemosynthesis is the process of using chemical energy to make carbon based molecules. Chemosynthesis is the process of using chemical energy to make carbon based molecules. This is because they are found in areas (ex: deep in the ocean ) that never receive light. This is because they are found in areas (ex: deep in the ocean ) that never receive light.