Cells and Energy

CHAPTER4@ CLASSZONE.COMKEY CONCEPTS Vocabulary Games Concept Maps Animated Biology Online Quiz4.1 Chemical Energy and ATPAll cells need chemical energy. Adenosine triphosphate(ATP) is the primary source of energyin all cells. ATP transfers energy for cell processessuch as building new molecules and transportingmaterials.4.2 Overview of PhotosynthesisThe overall process of photosynthesis producessugars that store chemical energy. Photosynthesisuses energy captured from sunlight to changecarbon dioxide and water into oxygen and sugars.Sunlight is absorbed during the light-dependentreactions, and sugars are made during the lightindependentreactions.4.3 Photosynthesis in DetailPhotosynthesis requires a series of chemicalreactions. Energy from sunlight is absorbed in thethylakoid membrane by photosystems II and I inthe light-dependent reactions. The energy istransferred to the Calvin cycle, which builds sugarmolecules from carbon dioxide.Synthesize Your Notes4.4 Overview of Cellular RespirationThe overall process of cellular respiration convertssugar into ATP using oxygen. Glycolysissplits glucose and when oxygen is present theproducts of glycolysis are used in cellular respiration.The Krebs cycle transfers energy to theelectron transport chain, which produces mostof the ATP in eukaryotic cells.mitochondrionThree-carbonmoleculeschloroplast6O 26H 2 O 6O 26CO 2ATP4.5 Cellular Respiration in DetailCellular respiration is an aerobic process withtwo main stages. The Krebs cycle breaks downcarbon-based molecules and transfers energy toelectron carriers. The electron carriers provideenergy to the electron transport chain. ATP is producedby the electron transport chain whenhydrogen ions flow through ATP synthase.4.6 FermentationFermentation allows the production of a smallamount of ATP without oxygen. Fermentationallows glycolysis to continue producing ATP whenoxygen is unavailable. Lactic acid fermentationoccurs in many cells, including human muscle cells.AND6H 2 OTwo-Column Chart Compare and contrast photosynthesisand cellular respiration. Use your notes to make detailedcharts that include details about both processes. Highlightimportant vocabulary and processes.PhotosynthesisCellular Respirationabsorbs sunlightproduces ATP6CO 2 +6H 2 O C 6 H 12 O 6 +6O 2 C 6 H 12 O 6 +6O 2 6CO 2 +6H 2 Ooccurs in chloroplasts occurs in mitochondriaConcept Map Use a concept map like the one below tosummarize and organize the processes of photosynthesis,cellular respiration, and fermentation.splitsglucoseglycolysisproduces2 ATP128 Unit 2: Cells