ATP Enter Date Aim: Cellular Respiration Warm-up: Where do we get our ENERGY from? HW: ATP 2007-2008

Energy needs of life Animals are energy consumers What do we need energy for? synthesis (building) reproduction active transport (pumping) 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? Energy is stored in organic molecules carbohydrates, fats, proteins GET organic molecules → FOOD digest food to get ENERGY (ATP) raw materials for building more molecules 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”

What is energy in biology? ATP Adenosine TriPhosphate 2007-2008

Harvesting energy stored in food Cellular respiration breaking down food to produce ATP In mitochondria using oxygen usually digesting glucose Movement of hydrogen atoms from glucose to water glucose + oxygen → carbon + water + energy dioxide C6H12O6 O2 CO2 H2O ATP → +

What do we need to make energy? The “Furnace” for making energy mitochondria Fuel food carbohydrates, fats, proteins oxygen “aerobic” The Helpers enzymes Make ATP! Make ATP! All I do all day… And no one even notices! food enzymes O2 ATP

Electron Acceptors! NAD and FAD Carry electrons as stored energy

“Burn fuels” to make energy CO2 + H2O + heat fuel (carbohydrates) O2 AEROBIC RESPIRATION -Making ATP energy by burning fuels in many small steps Movement of hydrogen atoms from glucose to water ATP O2 food (carbohydrates) CO2 + H2O + ATP

Using ATP to do work? Can’t store ATP too unstable only used in cell that produces it only short term energy storage Adenosine TriPhosphate work Adenosine DiPhosphate ADP + P A working muscle recycles over 10 million ATPs per second

{ { { ATP A Body’s Energy Budget eat food synthesis (building) storage • energy needed even at rest • activity • temperature control { eat food • growth • reproduction • repair { synthesis (building) • glycogen (animal starch) • fat { storage

What if oxygen is missing? Fermentation (anaerobic respiration) 1) ALCOHOL fermentation yeast glucose → ATP + CO2+ alcohol make beer, wine, bread

food H2O O2 enzymes ATP CO2