Re cap 5 minutes - write a summary (can use diagrams) of what you can recall from last weeks lesson.

Learning objectives ● Be able to describe exothermic and endothermic chemical reactions ● Be able to explain the importance of coupled chemical reactions in metabolism ● Be familiar with the terms oxidation and reduction

Energy in Chemical Reactions Energy progress of reaction Energy Content of reactants Energy Content of products Energy progress of reaction Energy Content of reactants Energy Content of products EXOTHERMIC ENDOTHERMIC

Enzymes work by lowering the energy of activation.

Coupled Chemical Reactions Coupling of exothermic and endothermic reaction allows energy released by reaction to start another Glucose Glucose – 6 - P ATPADP + Pi energy

OXIDATIONREDUCTION - Addition of oxygen- Removal of oxygen - Loss of hydrogen- Gaining hydrogen - Loss of electrons- Gaining electrons OILRIG Oxidation is the loss of electrons; reduction is the gain of electrons

CO 2 + H 2 O C 6 H 12 O 6 + O Respiration is the oxidation of carbon (glucose) NAD and FAD are electron acceptors during respiration NAD + + e - NADH + H + FAD + e - FADH 2

NAD + + e - NADH + H + FAD + e - FADH 2 Oxidised or reduced? reduced Reduced NADH and FADH 2 are important as they carry electrons which power other stages of respiration.

Class activity Nicotinamide adenine dinucleotide (NAD) Flavin adenine dinucleotide (FAD) NAD NADH FADH 2 FAD

Class activity Move around the class displaying what you are? Oxidised or reduced? How could we develop this idea?

Learning objectives ● Be able to describe exothermic and endothermic chemical reactions ● Be able to explain the importance of coupled chemical reactions in metabolism ● Be familiar with the terms oxidation and reduction

NADNADH FADH 2 FAD

Learning objectives ● Be able to draw a schematic overview of cellular respiration ● Be able to describe the metabolic pathway from glucose to pyruvate during glycolysis ● be able to analyse the energy transduction that occurs during glycolysis

Cell Metabolism Respiration: overview

Cell Metabolism Respiration: overview Glucose GLYCOLYSIS FERMENTATION LINK REACTION KREB CYCLE ELECTRON TRANSPORT CHAIN ANAEROBIC AEROBIC O2O2 H2OH2O

PP Glucose PP

PP PPPP

PP Phosphorylated glucose Stage 1: Activation of glucose By phosphorylation Stage 2: Splitting of Phosphorylated glucose PP Triose phosphate ATP ADP

PP Triose phosphate Pyruvate NAD + NADH NAD + NADH + ADP ATP P + ADP ATP P ADP + ATP P ADP + ATP P Stage 3: Oxidation of the triose phosphate Stage 4: Production of ATP

Yield from InputOutput Glucose 2 ATP4 ATP 2 Pyruvate 2 NADH 2 NAD GLYCOLYSIS

Learning objectives ● Be able to draw a schematic overview of cellular respiration ● Be able to describe the metabolic pathway from glucose to pyruvate during glycolysis ● be able to analyse the energy transduction that occurs during glycolysis

Learning objectives ● Be able to describe the difference between aerobic and anaerobic respiration ● Be able to recall which different subcellular compartment are involved in aerobic and anaerobic respiration ● Be able to explain the biological importance of anaerobic respiration

Cytoplasm Mitochondria Anaerobic Respiration Glucose GLYCOLYSIS LINK REACTION KREB CYCLE ELECTRON TRANSPORT CHAIN AEROBIC O2O2 H2OH2O

Glucose GLYCOLYSIS LINK REACTION KREB CYCLE ELECTRON TRANSPORT CHAIN AEROBIC O2O2 H2OH2O O2O2

Glucose GLYCOLYSIS LINK REACTION KREB CYCLE ELECTRON TRANSPORT CHAIN AEROBIC

Cytoplasm Mitochondria Anaerobic Respiration Glucose GLYCOLYSIS FERMENTATION Why does Anaerobic respiration occur?

Why does Anaerobic respiration occur? Anaerobic Respiration ● To enable continued glycolysis ● To recycle NAD for glycolysis ● Note, there is NO production of ATP (energy) during anaerobic respiration.

Anaerobic Respiration Two types of anaerobic respiration Alcoholic fermentationLactic acid fermentation

Alcoholic fermentation glucose triose phosphate pyruvate NAD NADH ethanalethanol CO 2 Producing ethanol from pyruvate regenerates oxidised NAD and allows glycolysis to continue NADHNAD Alcohol dehydrogenase

Lactic acid fermentation glucose triose phosphate pyruvate NAD NADH lactate Producing lactate from pyruvate regenerates oxidised NAD and allows glycolysis to continue NADHNAD lactate dehydrogenase Oxygen Debt?

Learning objectives ● Be able to describe the difference between aerobic and anaerobic respiration ● Be able to recall which different subcellular compartment are involved in aerobic and anaerobic respiration ● Be able to explain the biological importance of anaerobic respiration

Learning objectives ● Be able to describe the reactions that occur as pyruvate enters the mitochondria ● Be able to explain the energy transduction during the link reaction

Glucose GLYCOLYSIS LINK REACTION KREB CYCLE ELECTRON TRANSPORT CHAIN AEROBIC H2OH2O Aerobic Respiration O2O2 ● with oxygen available the pyruvate enters the mitochondria

Glucose LINK REACTION AEROBIC H2OH2O Aerobic Respiration O2O2

LINK REACTION Pyruvate Acetyl CoA CO 2 NAD NADH ● Remember glycolysis produces 2 molecules of pyruvate per molecule of glucose. Coenzyme A (CoA)

Yield from LINK REACTION InputOutput 2 pyruvate 2 CO 2 2 Acetyl CoA 2 NADH 2 NAD

Learning objectives ● Be able to describe the reactions that occur as pyruvate enters the mitochondria ● Be able to explain the energy transduction during the link reaction