ATP, Photosynthesis, & Cellular Respiration Chapter 9 Notes ATP is the high energy organic molecule used by all cells to perform their daily functions. ATP stands for ADENOSINE TRIPHOSPHATE! What is the structure of ATP? ATP consists of an adenine molecule, a ribose sugar, and 3 phosphate groups (draw in notes from the board) Copyright Cmassengale What Does ATP Do for You? It supplies YOU with ENERGY! Copyright Cmassengale Where is the energy found in the ATP molecule? The energy in ATP is stored in the bonds between the phosphate molecules! Chemical Bond Demonstration! • Chemical bonds are like stretched rubber bands – They are full of potential energy and when you release the rubber band all of that energy is released! How do you release that energy? • Breaking the high-energy bonds between the last two phosphates releases the energy so the cell can use it! What breaks the bond? -An enzyme called ATPase breaks the bond - When a phosphate is removed from ATP the molecule ADP (adenosine diphosphate) is formed and energy is released So now we have a bunch of ADP in the cell. But the cell needs a constant supply of energy which it gets from ATP!!!! So how do we remake ATP from ADP? Another enzyme called ATPsynthase is used which puts the phosphate back on! ATP to ADP Cycle • Draw From Board ATP is made all of the time in cells - The process that makes ATP is called Cellular Respiration - Cellular respiration occurs in both plants & animals ATP to ADP Cartoon Activity • Read the information and follow the instructions. • Use the example on the board as a guide • Color your cartoon. 9.2 Notes: Photosynthesis Photosynthesis is one of the most important chemical reactions on our planet What is Photosynthesis? Photosynthesis is a chemical reaction process that autotrophs like plants must do to make the sugar glucose. Glucose is then used to make ATP in cellular respiration Defining Photosynthesis • It is the process of changing light energy into chemical energy –The chemical energy is the carbohydrate (sugar) glucose The equation for the chemical reaction of photosynthesis • DRAW from board into notes Where does photosynthesis happen? • Photosynthesis happens in the chloroplasts of plants • The green pigment chlorophyll which absorbs light energy is the main pigment in chloroplasts Diagram of key parts in photosynthesis draw from board Why is photosynthesis important? 1) It provides plants with glucose 2) Animals eat the plants which supplies animals with glucose - Plants are the first step in the energy pyramid 3) The oxygen released during photosynthesis is used by all living things to do aerobic respiration 4) It removes carbon dioxide form the atmosphere and keeps the carbon cycle in balance Waterweed Simulation Lab • What factors affect photosynthesis? • Measuring amount of photosynthesis by counting the bubbles of oxygen produced by waterweed (elodea plant) • Looking at three factors: – Light color – Light intensity – Carbon dioxide levels Notes 9.3 Cellular respiration Cellular respiration is the process of making ATP from glucose. What is Cellular Respiration? Once glucose is acquired either by photosynthesis or consuming other organisms, an organism has to transform the glucose energy into a form that can be used by the organism called called ATP. This process is called cellular respiration Facts about Cellular Respiration 1) It is the breakdown of glucose molecules to make ATP 2) Takes place in all living things 3) May use oxygen - called AEROBIC Respiration – Very efficient makes 36 ATP per glucose 4) May not use oxygen – called ANAEROBIC respiration – Not efficient: only 2 ATP per glucose Facts about Aerobic respiration 1) Must have oxygen! 2) Very efficient – best way to make ATP because it makes a net of 36 ATP! 3) Must have mitochondria to do it! What is the chemical equation for aerobic cellular respiration? • Draw from board Steps in Aerobic Cellular Respiration What 1. Glycolysis 2. Citric Acid Cycle (Krebs Cycle) 3. Electron transport chain (E.T.C.) Where Oxygen # of net needed? ATP cytoplasm Anaerobic 2 NO! mitochondria Aerobic 2 YES! mitochondria Aerobic YES! 32 Total ATP produced 36 What happens during aerobic respiration? • Draw from board But what happens if no oxygen is present, our cells run out of oxygen or an organism doesn’t have mitochondria like bacteria? Without oxygen, cells have to make ATP anaerobically in ANAEROBIC RESPIRATION also called FERMENTATION! Facts about Anaerobic Respiration 1) Only way organisms like yeast (a eukaryote) and bacteria (prokaryotes) can make ATP! 2) No oxygen required! 3) Very inefficient – only 2 ATP produced instead of 36! 4) Another term for anaerobic respiration is FERMENTATION Facts about Fermentation Type 1) Lactic acid fermentation- happens in our muscle cells run out of oxygen – Produces only 2 ATP – Produces painful buildup of lactic acid in our cells Type 2) Alcoholic fermentation – done by yeast and one way to make beer and wine. – Produces carbon dioxide (beer bubbles) and alcohols – Produces only 2 ATP