1. Aerobic and anaerobic cell respiration

2.  What does respiration mean?  can mean breathing or ventilation of lungs or gills  Can refer to gas exchange in the blood at the cellular level (oxygen in/carbon dioxide out)  Can refer to the complex set of reactions that allow cells to burn sugar to make ATP

4.  What systems of the body are responsible for carrying these reactions out?  Respiratory (oxygen/carbon dioxide exchange)  Cardiovascular (transport)  Digestive (digestion and absorption of glucose)  We can “burn” molecules other than glucose  There are MANY steps in this process. Balanced equation is simplified

5.  Three general reactions- aerobic cell respiration  Glycolysis – happens in cell cytoplasm  Kreb’s Cycle – happens in matrix of mitochondria  Oxidative Phosphorylation/ETC- occurs in proteins in inner mitochondrial membrane called the Electron Transport Chain

8.  Splitting of sugar  Glucose split into two three carbon molecules called pyruvate and energy is released.  Energy is used to make 2 ATP by substrate Level Phosphorylation- ATP made without ETC  Energy is also used to make 2 NADH-an energy storage molecule to be “cashed out” later  No oxygen needed in this step!

9.  Each pyruvate is broken down into 3 CO2 molecules  Energy stored in  4 NADH  1 FADH2 (also a “check” to be cashed out)  1 ATP ( made by SLP- no ETC)  Is a cycle – begins and ends with same molecule How many times must the cycle run/glucose?

10.  Cycle turns twice for each glucose  8 NADH  2 FADH2  2ATP  6CO2

11. PHASEATPNADHFADH2 GLYCOLYSIS2 by SLP20 KREB’S CYCLE 2X per glucose 2 by SLP82 ETC?????00

12.  Energy rich electrons stored in NADH and FADH2 are cashed in at a cascade of proteins in the inner mitochondria membrane  As electrons fall they lose energy- exergonic  Energy released is COUPLED with the active transport of H+ ions across the membrane  Called chemiosmosis

14.  Oxygen accepts the electron at the end of the chain- H+ combine with oxygen and the electron to make water (waste)  H+ accumulate in intermembrane space  Rush back to matrix through ATP synthase- (light bulb shaped protein) release lots of energy  Energy is used to add a phosphate to ADP to make ATP !!!  This is called oxidative phosphorylation

15.  Phosphorylation- to make ATP  Oxidative – using oxygen as last electron acceptor (ETC)  Substrate level- without ETC, using enzymes in the mitochondria and cytoplasm

16. PhaseATPNADHFADH2 Glycolysis22 (worth 2 ATP each) 0 KREB’S28 (worth 3 ATP each) 2 (worth 2 ATP each) ETC cash out value N/A4 ATP + 24 ATP= 28 ATP 4 ATP TOTAL ATP = 36 / glucose

17.  2 from glycolysis are only worth 2 ATPs.  They have to travel through two mitochondrial membranes  8 NADHs from Kreb’s are already in mitochondria – are worth 3 ATPs each  Prokaryotes make 38 ATPs – no internal membranes to pass through