Cell Respiration Pre-Lab due Wednesday February Root Word Quiz 2/11 Cellular Energetics Metabolism Reading Guide Metabolism Lectures Metabolism Picture Packets Free Energy Practice Problems Metabolism Quiz Enzyme Pre-Lab Enzyme Lab Report due 1/25/16 Enzyme Quiz Enzyme FRQ TODAY! Cellular Respiration Week-Long (Chapter 9) due Monday Cellular Respiration Lectures – not finished yet Cell Respiration Pre-Lab due Wednesday February Root Word Quiz 2/11

Graph data and calculate the reaction rate. ENZYME FRQ STUDY GUIDE Graph data and calculate the reaction rate. Explain why a change in reaction rate was observed after so many minutes. Draw and label another line on the graph to predict the results if the concentration of the enzyme was doubled. Explain results. Identify TWO environmental factors that can change the rate of enzyme-mediated reactions. Discuss how each of those two factors would affect the reaction rate of an enzyme.

Cellular Respiration 2007-2008

What’s the point? The point is to make ATP! ATP 2007-2008

glucose      pyruvate Step 1: Glycolysis Breaking down glucose “glyco – lysis” (splitting sugar) ancient pathway which harvests energy where energy transfer first evolved transfer energy from organic molecules to ATP still is starting point for all cellular respiration but it’s inefficient generate only 2 ATP for every 1 glucose occurs in cytosol anaerobic process glucose      pyruvate 2x 6C 3C Why does it make sense that this happens in the cytosol? Who evolved first?

Evolutionary Perspective Prokaryotes first cells had no organelles (NO MITOCHONDRIA) Anaerobic atmosphere life on Earth first evolved without free oxygen (O2) in atmosphere energy had to be captured from organic molecules in absence of O2 Prokaryotes that evolved glycolysis are ancestors of all modern life ALL cells still utilize glycolysis The enzymes of glycolysis are very similar among all organisms. The genes that code for them are highly conserved. They are a good measure for evolutionary studies. Compare eukaryotes, bacteria & archaea using glycolysis enzymes. Bacteria = 3.5 billion years ago glycolysis in cytosol = doesn’t require a membrane-bound organelle O2 = 2.7 billion years ago photosynthetic bacteria / proto-blue-green algae Eukaryotes = 1.5 billion years ago membrane-bound organelles! Processes that all life/organisms share: Protein synthesis Glycolysis DNA replication

OVERVIEW 10 reactions convert glucose (6C) to 2 pyruvate (3C) produces: 4 ATP & 2 NADH consumes: 2 ATP net: 2 ATP & 2 NADH

Glycolysis summary 4ATP endergonic invest some ATP exergonic ENERGY INVESTMENT G3P C-C-C-P exergonic harvest a little ATP & a little NADH ENERGY PAYOFF 4ATP Glucose is a stable molecule it needs an activation energy to break it apart. phosphorylate it = Pi comes from ATP. make NADH & put it in the bank for later. like $$ in the bank yield 2 ATP 2 NADH NET YIELD

First part of Glycolysis GLUCOSE ENDERGONIC!!! Why?????? 2-pgal Input of energy

ExerGONIC!!! 2-pgal Why?????? Releasing energy 2-pyruvates

Hard way to make a living! IS THAT IT?! Not a lot of energy… for 1 billon years+ this is how life on Earth survived no O2= slow growth, slow reproduction only harvest 3.5% of energy stored in glucose more carbons to strip off = more energy to harvest O2 glucose     pyruvate O2 So why does glycolysis still take place? 6C 2x 3C O2 Hard way to make a living! O2 O2

CELLULAR RESPIRATION Step 2 THE CITRIC ACID CYCLE (TCA) OR THE KREB’S CYCLE

Occurs in mitochondrial matrix The most important link to the electron transport chain (ETC makes a ton of ATP) Occurs in mitochondrial matrix Some bacteria too (takes place in cytoplasm) Sir Hans Adolf Krebs, 1937 BETWEEN GLYCOLYSIS AND CITRIC ACID CYCLE: Coenzyme A pyruvate acetyl-CoA Kreb’s Cycle NADH CO2

Initiating step of Citric Acid Cycle: 4-C oxaloacetic acid + 2-C acetyl CoA 6-C citric acid During the cycle: Citric acid rearranged; Stripped of 2-Cs CO2 released 4 e- released to electron carriers (NAD+ and FAD) 1 molecule of oxaloacetic acid remains to begin the cycle again 1 ATP made Oxidation Reactions!!! molecules that lose electrons…LEO goes GER Loss of electrons at 4 specific places…to fuel ETC Use NAD+ and FAD Steps 4, 6, 10 (NAD+) & 8 (FAD)

2 ATP O2 in 1 3 e- in 2 NADH 2 H2Oout CO2 out 30+ ATP 2 ATP

CELLULAR RESPIRATION Step 3 THE ELECTRON TRANSPORT CHAIN (ETC)

High yield of energy Occurs in inner membrane of mitochondria 2 H+ + 2 e+ + 1/2 O2 ---> H2O + energy Small oxidation steps accomplish the conversion of ADP to ATP A series of coupled reactions Referred to as oxidative phosphorylation Energy is used (endergonic) to pump H+ UP the concentration gradient out the mitochondria through 4 protein complexes Final electron acceptor = oxygen (turns to water) on 4th protein (cytochrome)

Proton Motive Force (PMF): increased concentration of H+ creates a force that pushes them through one last protein complex ATP synthase exergonically uses H+ concentration gradient to phosphorylate ADP (chemiosmosis) 32-34 ATP molecules are made per glucose

OXIDATIVE PHOSPHORYLATION Each NADH = Each FADH2 =

Substrate Level Phosphorylation Oxidative Phosphorylation Glycolysis 2 ATP 2 NADH = 6 ATP Transition Reaction 0 ATP Kreb’s Cycle 6 NADH = 18 2 FADH2 = 4 ATP Total ATP 4 ATP 34 ATP VS. Net ATP Production Per Glucose

ANAEROBIC RESPIRATION Count the carbons!! Lactic acid is not a dead end like ethanol. Once you have O2 again, lactate is converted back to pyruvate by the liver and fed to the Kreb’s cycle.

Fermentation 2 oxygen 2 pyruvates glucose O2 NADH builds up in the system !!! Creates an NAD+ shortage (necessary for glycolysis) 2 Types of Anaerobic Respiration: alcoholic & lactic acid

2 pyruvate  2 acetylaldehyde  2 ethanol Alcohol Fermentation 2 pyruvate  2 acetylaldehyde  2 ethanol 3C 2 CO2 2C NADH NAD+  glycolysis Occurs in bacteria, yeast, fungi Makes beer, wine, bread Dead end process at ~12% ethanol, kills yeast can’t reverse the reaction

Lactic Acid Fermentation 2 pyruvate  2 lactate 3C 3C NADH NAD+  glycolysis Occurs in humans and animal muscle cells when oxygen is not available Pyruvate reduced to lactate NAD+ regenerated for glycolysis Muscle cramps come from acid build-up in cells REVERSIBLE!! Lactate converted back to pyruvate by liver when oxygen is available!

Pyruvate is a branching point!!! fermentation anaerobic respiration mitochondria Kreb’s cycle aerobic respiration

IMPORTANT DATES Tuesday 2/2: Anaerobic Respiration; KAHOOTS; Read Lab Procedures for homework Wednesday, 2/3: Set up Cellular Respiration Lab Trays Thursday, 2/4: Cellular Respiration Quiz (all five parts) Glycolysis Pyruvate Oxidation Krebs ETC Anaerobic Respiration Friday, 2/5: Assembly!? Lab Procedures Review; Photosynthesis Packet due Friday (no textbook). Monday, 2/8: Cellular Respiration Lab

Lab Objectives Calculate the rate of respiration. Demonstrate the relationship of the gas laws to the function of a respirometer. Investigate the effect of temperature on cell respiration. Investigate the effect of germination and non-germination on cell respiration. Understand the significance of a control in experimental processes. Calculate the rate of respiration. Design an experiment to measure cell respiration.

CREATE A GOOD, SCIENTIFIC, & INFORMATIVE TITLE!! KEY USE CORRECTED DIFFERENCE!!! mL of Oxygen consumed Graphing data over time? Hmm… what kind of graph will it be?! time (minutes)