 Metabolism › Sum of all chemical changes/reactions in an organism  Photosynthesis › Conversion of light energy (E) into sugars (a form of chemical E)  Cellular respiration › A metabolic process in which organisms obtain E from sugars; glucose (C6H12O6), the suagr is broken down to generate ATP.  ATP › Adenosine triphosphate, an energy molecule found in ALL LIVING CELLS

Section 1

 Plants are primary producers  They use direct sunlight for energy through a process called photosynthesis  Autotrophic vs. heterotrophic

 PLANT cells use the energy in sunlight to to make food (glucose) from carbon dioxide and water  Photosynthesis takes place in chloroplasts 6CO 2 + 6H 2 O +sunlight  C 6 H 12 O 6 + 6O 2

 ALL cells obtain energy from food  The food (glucose) is broken down into CO 2 and H 2 O, and energy (ATP) is released  Cellular respiration takes place in the mitochondria C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + energy

Photosynthesis Cellular Respiration  Uses light energy to make glucose  Uses carbon dioxide  Uses water  Makes oxygen  Happens in chloroplasts 6CO 2 + 6H 2 O + sunlight  C 6 H 12 O 6 + 6O 2 C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + energy  Uses glucose to make energy (ATP)  Makes carbon dioxide  Makes water  Uses oxygen  Happens in mitochondria

Section 2

 Thylakoids are flattened membranes in sacs (in system)  Grana are stacks of thylakoids(in chloroplast)  Stroma is the solution surrounding the thylakoids › Site for Calvin Cycle

 Chlorophyll › Two types: chlorophyll a and chlorophyll b  Accessory pigments › Carotenoids: absorb blue and green, reflect yellow, orange and red › Xanthophylls  these are the pigments you seen in the fall!

red orange yellowgreen blue purple

 3 major types of photosynthetic organisms: › Plants › Protista › Bacteria  Specifically in plants exist organelles called chloroplasts which contain chlorophyll  Chloroplasts are the site for photosynthesis and conversion of sunlight to glucose (C 6 H 12 O 6 )  This E conversion occurs in the thylakoids inside the chloroplasts

 Involves a complex set of chemical reactions that form a biochemical pathway  During photosynthesis, autotrophs manufacture organic compounds from CO 2, H 2 O and sunlight

1. Electron Transport Chains (Light Dependent Reactions) 2. Chemiosmosis 3. Calvin Cycle

 Clusters of pigment molecules  Two types: › Photosystem I and photosystem II › Main difference between them is in their wavelengths  Purpose: produce ATP and NADPH

 Synthesis of ATP  ATP synthase makes ATP by adding a phosphate group to ADP during chemiosmosis › The energy that drives this reaction is provided by the movement of protons from the inside of the thylakoid membrane to the stroma

Acts as an enzyme catalyzing the synthesis of ATP from ADP Also acts as a carrier protein moving protons across the thylakoid membrane

 Named after a scientist  Putting the stored energy (NADPH) to work!  Organic compounds are produced using stored energy in ATP and NADPH (made during the light reactions)  Consumes 9 molecules of ATP and 6 molecules of NADPH for each molecule of glucose

 Light Reactions (Electron Transport Chain) › Produces stored energy in the form of ATP and NADPH from light energy › Input: light energy › Output: ATP, NADPH  Calvin Cycle › Produces organic compounds, using the energy stored in ATP and NADPH during the light reactions › Input: ATP, NADPH, CO 2 › Output: organic compounds (sugar) 6CO 2 + 6H 2 O +sunlight  C 6 H 12 O 6 + 6O 2

 Electron Transport Chain › Light dependent reaction › Occurs in thylakoid membrane › Inputs: H 2 O, sunlight, NADP + › Outputs: O 2, NADPH  Chemiosmosis › Light dependent reaction › Occurs in thylakoid membrane › Input: protons, ADP › Output: ATP  Calvin Cycle › Occurs in stroma › Input: ATP, NADPH, carbon dioxide (CO 2 ) › Output: glucose, ADP, NADP +

Section 3

 All eukaryotic cells obtain energy from food  The food (glucose) is broken down to CO 2 and H 2 O, and energy (ATP) is released  Cellular respiration takes place in the mitochondria C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + energy

 Breakdown or splitting of glucose (6 carbons) into TWO 3-carbon molecules called pyruvic acid  DOES NOT need oxygen in any of its chemical reactions  Serves as first step in a variety of anaerobic and aerobic reactions  Happens in CYTOPLASM of cells  The ONE metabolic pathway found in ALL living organisms  Net yield of two ATP molecules for every molecule of glucose that is converted into pyruvic acid

 New bellringer page! Week of Dec. 12  How are the products of photosynthesis and cellular respiration related?  What organisms do cellular respiration?  Bio 2: take out chapter 6 vocab (due today!)

 Prokaryotes: takes place in cytosol of the cell  Eukaryotes: takes place in the mitochondrial matrix  BEFORE BEGINNING KREBS: Pyruvic acid diffuses across the double membrane of the mitochondria into the mitochondrial matrix where it reacts with a molecule called coenzyme A to form acetyl CoA  Acetyl CoA is the input for the Krebs cycle!!!

Glycolysis Krebs Cycle Prep for Krebs cycle Glucose Pyruvic acid Acetyl CoA Pyruvic acid Acetyl CoA

 One glucose molecule produces TWO acetyl CoA molecules  Therefore one molecule of glucose can “turn” the Krebs cycle two times  Krebs cycle input: 2 acetyl CoA  Krebs cycle output: › 6 molecules of NADH › 2 molecules of FADH 2 › 2 molecules of ATP › 4 molecules of CO 2

 Pyruvic acid molecules are turned into some “waste” product  Occurs in anaerobic situations  Two of the most common types of fermentation are: › Lactic acid › Alcoholic

 Done by some fungi, some bacteria like the Lactobacillus acidophilus in yogurt, and sometimes by our muscles  3-carbon pyruvic acid turned into lactic acid  This process is used to make cheese and yogurt  Once our muscle form lactic acid, they cannot do anything else with it, so until it is washed away by the blood stream and carried to the liver (which is able to get rid of it) it just sits in muscles

 Done by yeast and some kinds of bacteria  The “waste” products of this process are ethanol and carbon dioxide (CO 2 )  This process is used in making bread, beer and wine

Lactic Acid Fermentation Alcoholic Fermentation  Input: pyruvic acid  Output: lactic acid  Organisms: fungi, bacteria, our muscle cells  Number of ATP: 2 ATP  Input: pyruvic acid  Output: ethanol and carbon dioxide  Organisms: yeast, some bacteria  Number of ATP: 2 ATP

 Concentration gradient drives the synthesis of ATP by chemiosmosis, the same process that generates ATP in photosynthesis  Input: NADH, FADH 2, O 2  Output: H 2 O, ATP, FAD +, NAD +  ATP produced when FADH 2 and NADH release hydrogen atoms  H 2 O formed when electrons, protons (H + ) and oxygen combine

Glucose and oxygen GlycolysisKrebs Cycle Electron Transport Chain Carbon dioxide, water, ATP

GlycolysisFermentation Lactic Acid Fermentation Alcoholic Fermentation Krebs Cycle Electron Transport Chain Anaerobic Aerobic

 38 ATP produced per one glucose molecule!!  The actual number of ATP molecules generated through aerobic respiration varies from cell to cell. Most produce 36 ATP molecules per glucose molecule

 66% efficiency compared to 3.5% efficiency of glycolysis  This means that aerobic respiration is 20 times more efficient than anaerobic!  It is even more efficient than a car engine which is only 25% efficient

 Cellular respiration provides the ATP that all cells need to support the activities of life  Cells also need specific organic compounds (sugars and starches) from which to build macromolecules, which do not always come from the food we eat  That is why glycolysis and the Krebs cycle are used by cells to make the compounds that are missing in food C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + energy