Cellular Respiration

(O 2 )energy organic molecules (glucose) energy (ATP), CO 2 water (H 2 O).An oxygen(O 2 ) requiring process that uses energy extracted from organic molecules (glucose) to produce energy (ATP), CO 2 and water (H 2 O). C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + energy glucose 36 ATP

Question: In what kinds organisms does cellular respiration take place?In what kinds organisms does cellular respiration take place?

Plants and Animals Plants - AutotrophsPlants - Autotrophs: self-producers. Animals - Heterotrophs: consumers.

Mitochondria Organellecellular respirationOrganelle where cellular respiration takes place. Inner membrane Outer membrane Inner membrane space Matrix Cristae

Breakdown of Cellular Respiration 3 main parts (reactions).3 main parts (reactions). 1. Glycolysis (splitting of sugar) a. cytosol, just outside of mitochondria.

Breakdown of Cellular Respiration 2. Krebs Cycle (Citric Acid Cycle) * occurs in mitochondrial matrix 3. Electron Transport Chain (ETC) 3. Electron Transport Chain (ETC) * inner mitochondrial membrane.

1. Glycolysis Occurs in the cytosol just outside of mitochondria. Two phases (10 steps):Two phases (10 steps): A. Energy investment phase (2 ATP to start) B. Energy yielding phase

1. Glycolysis A. Energy Investment Phase: Glucose (6C) Glyceraldehyde phosphate (2 - 3C) (G3P or GAP) 2 ATP - used 0 ATP - produced 0 NADH - produced 2ATP 2ADP +P C-C-C-C-C-C C-C-C

1. Glycolysis B. Energy Yielding Phase Glyceraldehyde phosphate (2 - 3C) (G3P or GAP) Pyruvate (2 - 3C) (PYR) 0 ATP - used 4 ATP - produced 2 NADH - produced 4ATP 4ADP +P

Fermentation “NO Oxygen” (called anaerobic).Occurs in cytosol when “NO Oxygen” is present (called anaerobic). glycolysisfermentationRemember: glycolysis is part of fermentation. Two Types:Two Types: 1.Alcoholic Fermentation 2. Lactic Acid Fermentation

Alcohol Fermentation Plants and Fungi  beer and winePlants and Fungi  beer and wine glucose Glycolysis CCCCCCCCCCCCC CCCCCC 2 Pyruvic acid 2ATP 2ADP + 2 2NADH P 2 NAD + CCCC 2 Ethanol 2CO 2 released 2NADH 2 NAD + Makes bread rise!

Alcohol Fermentation End Products: Alcohol fermentationEnd Products: Alcohol fermentation 2 - ATP (substrate-level phosphorylation) 2 - CO Ethanol’s

Lactic Acid Fermentation Animals (pain in muscle after a workout).Animals (pain in muscle after a workout). 2 Lactic acid acid 2NADH 2 NAD + CCCCCC Glucose Glycolysis CCCCCC 2 Pyruvic acid 2ATP 2ADP + 2 2NADH P 2 NAD + CCCCCCCCCCCCC

Lactic Acid Fermentation End Products: Lactic acid fermentationEnd Products: Lactic acid fermentation 2 - ATP 2 - Lactic Acids (causes muscle fatigue)

2. Krebs Cycle (Citric Acid Cycle) Location:Location: mitochondrial matrix. It takes 2 turns of the krebs cycle to convert glucose molecule. Mitochondrial Matrix Aerobic respiration (with oxygen) occurs in the mitochondria

2. Krebs Cycle (Citric Acid Cycle) Krebs Cycle 1 Acetyl CoA (2C) 3 NAD + 3 NADH FAD FADH 2 ATP ADP +P (one turn) OAA (4C) Citrate (6C) 2 CO 2

2. Krebs Cycle (Citric Acid Cycle) Krebs Cycle 2 Acetyl CoA (2C) 6 NAD + 6 NADH 2 FAD 2 FADH 2 2 ATP 2 ADP +P (two turns) OAA (4C) Citrate (6C) 4 CO 2

2. Krebs Cycle (Citric Acid Cycle) 2 turnsTotal net yield (2 turns of krebs cycle) ATP (substrate-level phosphorylation) 2.H+ Carrier  6 – NADH 3.H+ Carrier  2 - FADH CO 2 Summary: Some CO2, Lots of energy carriers, some ATP

3. Electron Transport Chain (ETC) and Oxidative Phosphorylation ( Chemiosmosis ) Location:Location: inner mitochondrial membrane. ETC pumps H + (protons) across inner membrane (lowers pH in inner membrane space). Inner Mitochondrial Membrane

3. Electron Transport Chain (ETC) ) diffusionThe H+ then move via diffusion (Proton Motive Force) through ATP Synthase to make ATP. Each NADH converts to 3 ATP. Each FADH 2 converts to 2 ATP (enters the ETC at a lower level than NADH).

3. Electron Transport Chain (ETC) Inner membrane Outer membrane Inner membrane space Matrix Cristae The ETC produces most of the ATP during aerobic respiration

3. ETC and Oxidative Phosphorylation ( Chemiosmosis for NADH )

3. ETC and Oxidative Phosphorylation (Chemiosmosis for 3. ETC and Oxidative Phosphorylation (Chemiosmosis for FADH 2 )

TOTAL ATP YIELD ATP - Glycolysis 2.34 ATP – Kreb’s Cycle & ETC 36 ATP - TOTAL YIELD ATP

Eukaryotes (Have Membranes) Total ATP Yield 02 ATP - glycolysis (substrate-level phosphorylation) 04 ATP - converted from 2 NADH - glycolysis 06 ATP - converted from 2 NADH - grooming phase 02 ATP - Krebs cycle (substrate-level phosphorylation) 18 ATP - converted from 6 NADH - Krebs cycle 04 ATP - converted from 2 FADH 2 - Krebs cycle 36 ATP - TOTAL

Maximum ATP Yield for Cellular Respiration (Eukaryotes) 36 ATP (maximum per glucose) Glucose Glycolysis 2ATP 4ATP 6ATP 18ATP 4ATP 2ATP 2 ATP (substrate-level phosphorylation) 2NADH 6NADH Krebs Cycle 2FADH 2 2 ATP (substrate-level phosphorylation) 2 Pyruvate 2 Acetyl CoA ETC and Oxidative Phosphorylation Cytosol Mitochondria

Question: In addition to glucose, what other various food molecules are used in Cellular Respiration?In addition to glucose, what other various food molecules are used in Cellular Respiration?

Catabolism of Various Food Molecules Other organic molecules used for fuel. 1. Carbohydrates: polysaccharides 2. Fats: glycerol’s and fatty acids 3. Proteins: amino acids