Cell Energetics: Photosynthesis & Respiration

1. Cell Energetics: Photosynthesis & Respiration

2. Carbon • Carbon forms millions of compounds, both simple and complex • All living things contain carbon • Living things cycle carbon from the air (inorganic gas form) to the solid form (organic) and back to the air • Light from the sun provides the energy for photosynthesis, the process of making organic compounds such as sugar • The sun’s energy is stored the chemical bonds of sugars and other carbohydrates • Carbohydrates are used by most living things to provide energy for LIVING

3. What is the Global Carbon Cycle? • The movement of carbon between the atmosphere, soil, ocean, living things, and fossil fuels • Carbon exists primarily as: • - Gas, carbon dioxide (CO2), in Earth’s atmosphere • - Organiccarbon in living and dead organisms. • Atmospheric carbon is constantly recycled, mostly by green plants and algae, to produce oxygen

4. Fossil fuel The Global Carbon Cycle CO2 & other greenhouse gases respiration Photosynthesis Green plants Emissions from burning fossil fuel Algae & cyanobacteria Dissolved carbon

5. Photosynthesis and Respiration in the Global Carbon Cycle Creates stored Energy-ATP Carbohydrates & Oxygen Photosynthesis Respiration Carbon dioxide & Water

6. Some organisms live in places that never get sunlight. In chemosynthesis, chemical energy is used to build carbon-based molecules. similar to photosynthesis uses chemical energy instead of light energy occurs where light cannot penetrate-deep ocean A few types of organisms do not need sunlight and photosynthesis as a sourceof energy. Biology-McDougal Littell 2008

7. Mitochondrion Nucleus Chloroplasts A cell has some remarkable organelles!!! Is this plant or animal?

8. Super Fun Activity! • Compare and contrast the structure and function of a chloroplast and a mitochondrion • Make a poster • Make a PowerPoint • Make a podcast • Make a storybook • Make a 3D model with explanation MC.3.B.1

9. The Chloroplast is Remarkable Organelle Stroma Thylakoid Stroma = space/matrix inside the chloroplast where carbohydrate is synthesized Thylakoid = structures with chlorophyll and light reaction center

10. The Basic Process of Photosynthesis light energy CO2 + H2O [CH2O] + O2 carbon dioxide water carbohydrates oxygen

11. Photosynthesis in chloroplast is divided into… The Light Reactions- Light Dependent The Dark Reactions- Light Independent

12. MUST occur in the presence of light The Light Reactions- Light Dependent CAN occur in the presence of light, but works better in the dark The Dark Reactions- Light Independent

13. light energy CO2 + H2O [CH2O] + O2 carbon dioxide water carbohydrates oxygen Keeping track of the oxygen atom in photosynthesis Cornelius van Niel (1897-1985) Standford University Used radioactive-labeled oxygen in water and unlabeled carbon dioxide in photosynthesis experiments Found that oxygen gas produced comes from water Postulated that the oxygen atom in carbohydrates must be from carbon dioxide

14. H2O O2 The Light Reactions ADP ATP NADP+ NADPH The Dark Reactions Carbohydrates CO2 + H2O MC.3.B.4

15. Where do the reactions happen inside the chloroplast? Light reaction occurs on thylakoid membranes H2O CO2 Light reaction Dark reaction Dark reaction occurs in the stroma O2 Carbohydrates MC.3.B.4

16. Frameworks Strand: Molecules and Cells Standard 3: Students shall demonstrate an understanding of how cells obtain and use energy (energetics).