What is the photosynthesis formula? DO Now What is the photosynthesis formula?

1. What are the stages of cellular respiration? 2. What are the difference between aerobic and anaerobic respiration?

Energy needs of life Animals need energy for… synthesis (building for growth) reproduction active transport movement temperature control (making heat) Which is to say… if you don’t eat, you die… because you run out of energy. The 2nd Law of Thermodynamics takes over!

Where do we get energy? ATP Energy is stored in organic molecules carbohydrates, fats, proteins Animals eat these organic molecules  food digest food to get fuels for energy (ATP) raw materials for building more molecules carbohydrates, fats, proteins, nucleic acids ATP We eat to take in the fuels to make ATP which will then be used to help us build biomolecules and grow and move and… live! heterotrophs = “fed by others” vs. autotrophs = “self-feeders”

ATP What is energy in biology? Adenosine TriPhosphate Whoa! HOT stuff! 2009-2010

Releasing the Energy (Break the Bond) ATP Break into ADP and P to release energy! ADP—adenosine diphosphate

Harvesting energy stored in food Cellular respiration: the process of breaking down food to produce ATP in mitochondria using oxygen “aerobic” respiration usually digesting glucose but could be other sugars, fats, or proteins ATP food O2 Movement of hydrogen atoms from glucose to water glucose + oxygen  energy + carbon + water dioxide C6H12O6 6O2 ATP 6CO2 6H2O  +

What do we need to make energy? The “Furnace” for making energy mitochondria Fuel food: carbohydrates, fats, proteins Helpers oxygen enzymes Product ATP Waste products carbon dioxide then used by plants water Make ATP! Make ATP! All I do all day… And no one even notices! food ATP enzymes CO2 H2O O2

Mitochondria are everywhere!! animal cells plant cells

How do we use ATP to do work? Can’t store ATP too unstable only used in cell that produces it only short term energy storage carbohydrates & fats are long term energy storage Adenosine TriPhosphate work Adenosine DiPhosphate ADP A working muscle recycles over 10 million ATPs per second Whoa! Pass me the glucose & oxygen!

The Steps of Respiration 1. Glycolysis (no oxygen required) 2. Kreb’s Cycle (oxygen required) 3. Electron Transport Chain (oxygen required)

Glycolysis Convert glucose  pyruvate Occurs in the cytoplasm Produces 2 net ATP

Kreb’s Cycle Occurs in the mitochondria Produces CO2 Produces 2 net per cycle ATP

Do Now What are the reactants and products of respiration?

Electron Transport Chain (ETC) Occurs in the mitochondria (inner membrane) requires OXYGEN Produces 32 net ATP

ETC ATP Synthase: enzyme that produces (from ADP + P) when protons pass through (passive transport) Proton gradient allows this to occur—as electrons travel down the ETC, protons are forced into the intermembrane space (active transport) OXYGEN is the final electron acceptor—produces H2O ATP ATP

How much energy are we talking? Cellular respiration produces a net total of 36 ! Glycolysis 2 Kreb’s Cycle 2 ETC 32 Total 36 ATP ATP ATP ATP ATP

What if oxygen is missing? No oxygen available = can’t complete aerobic respiration Anaerobic respiration also known as fermentation alcohol fermentation lactic acid fermentation no oxygen or no mitochondria (bacteria) can only make very little ATP large animals cannot survive yeast bacteria

Anaerobic Respiration Fermentation alcohol fermentation yeast glucose  ATP + CO2+ alcohol make beer, wine, bread lactic acid fermentation bacteria, animals glucose  ATP + lactic acid bacteria make yogurt animals feel muscle fatigue Tastes good… but not enough energy for me!

Do Now Write down the stages of cellular respiration and the amount of produced at each stage Glycolysis 2 Kreb’s Cycle 2 ETC 32 Total 36 ATP ATP ATP ATP ATP

Aerobic v. Anaerobic Respiration

Balloon and Yeast Demo Fact: Yeast undergo respiration PREDIT: What will happen to the balloon when I mix yeast and sugar in warm water? ANALYZE: 1. Why did the balloon swell up? 2. Why did I add sugar to the yeast?

What happens when we DON’T have O2?? Anaerobic respiration!!! Definition: a form of Cellular Respiration that occurs when O2 is absent or scarce. A.k.a. fermentation Only occurs in microorganisms

Fermentation allows glycolysis to continue Note: Fermentation itself does not produce ATP—it allows glycolysis to continue, which produces 2 ATP

Anaerobic Respiration: WHERE does it occur?

Anaerobic Respiration: 2 Versions Lactic Acid Fermentation Alcohol Fermentation Produces… Lactic acid (C3H6O3) Occurs during high-intensity exercise Occurs in your muscle cells Also in bacteria and fungi Produces… Ethanol CO2 CO2 accounts for the carbonation (the bubbles!) Occurs in yeast and in bacteria High energy demands of intense exercise exceed aerobic capacity of muscle cells, so get ATP from anaerobic reps Lactic acid dissociates in lactate and H+, so decreases pH of blood (acidosis), causes muscle fatigue (reduces muscles’ abilities to contract)—contested in some studies!! Lactic acid fermentation—once O2 is available, body breaks down lactic acid and removes it from cells. Breath hard after you stop exercising to make up for the lost O2 you had been experiencing during hard exercise!

Lactic Acid Fermentation Let's hear from the Dr.’s

Alcohol Fermentation

Other effects of fermentation Bacteria use lactic acid to sour the milk in yogurt Bacteria and mold undergo fermentation to convert milk to cheese…the different biproducts of fermentation give cheeses their distinct smells Yeast causes bread dough to rise Thinking question…why would yeast undergoing fermentation cause the dough to rise???? Also, bacteria inside your body undergo fermentation b/c no O2 is available…these microorganisms are in digestive tract of animal, these microorganisms breaking down materials allows us to absorb more nutrients from food

STOP AND THINK Why do you use yeast to make bread dough rise? Why does it make sense that bacteria in your digestive tract undergo fermentation? no O2 is available…these microorganisms are in digestive tract of animal, these microorganisms breaking down materials allows us to absorb more nutrients from food

Guess Who?: Fermentation Edition

Guess Who?? 1. occurs in this organelle: 2. can occur in the absence of O2 Anaerobic anaerobic

Guess Who?? 3. occurs here: 4. produces CO2 as a product 5. produces ~36 ATP 3. Anaerobic 4. Both 5. anaerobic

Guess Who?? 6. Accounts for the burn you feel in your muscles when you exercise 7. Can make beer 8. Involves the ETC 9. Is much less energy-efficient 10. O2 is the final electron acceptor 11. Allows glycolysis to continue. 6. Anaerobic 7. Anaerobic 8. aerobic 9. Anaerobic 10. aerobic 11. Anaerobic

Group Activity (~10 minutes) Create a concept map in your groups using the notecards provided! Fill in yourself the appropriate # of ATP molecules.

Lactic Acid Fermentation Glucose Glycolysis(cytosol) O2 Present Aerobic Respiration ~36 ATP CO2 No O2 Present Lactic Acid Fermentation 2 ATP Lactic acid Alcohol Fermentation Ethanol

Exit Slip How do we differentiate between Aerobic and Anaerobic Respiration? Provide at least 3 reasons.