CELLULAR RESPIRATION Chapter 9

WHAT IS IT? A Process of breaking down food (sugar/glucose) in our cells to release energy (ATP) in order to use it to do work. Main Goal  Make ATP

WHAT ARE THE TYPES? 2 types of Cellular Respiration  Anaerobic Respiration not  Occurs when oxygen is not present!  Aerobic Respiration is  Uses Oxygen, occurs when oxygen is present

AEROBIC RESPIRATION Equation:  Glucose + Oxygen  Carbon Dioxide + Water + ATP  C 6 H 12 O 6 + O 2  CO 2 + H 2 O + ATP

WHAT ARE THE STAGES IN EACH? Anaerobic – 2 stages  Glycolysis  Fermentation Aerobic – 3 stages  Glycolysis  Krebs Cycle  Electron Transport Chain

Cellular Respiration AnaerobicGlycolysisFermentationAerobicGlycolysisKrebs Cycle Electron Transport Chain Without Oxygen With Oxygen

WHAT DO BOTH ANAEROBIC & AEROBIC RESPIRATION START WITH? Glycolysis!

GLYCOLYSIS Location: Cytoplasm of the Cell Summary: The process in which 1 molecule of glucose is broken into 2 molecules of pyruvic acid. Steps: 1.Glucose 1.Glucose is split in half  2 molecules called PGAL. 2.Each PGAL is then converted into a molecule called Pyruvic acid.How? a)Each PGAL loses a hydrogen (H) b)These hydrogens get picked up by NAD  NADH 3.From all this 2 ATP are needed/used & 4 ATP are made! 4.That gives us a net total of 2 ATP !

GLYCOLYSIS Go to Page 255. Let’s draw this! Glucose (6 carbons)

GLYCOLYSIS Glucose (6 carbons) PGAL (3 carbons) 1

GLYCOLYSIS Glucose (6 carbons) PGAL (3 carbons) 1 2 Pyruvic Acid (3 carbons)

GLYCOLYSIS Glucose (6 carbons) PGAL (3 carbons) 1 Pyruvic Acid (3 carbons) Lose a “H” = 2 “H” + 2NAD  2NADH

GLYCOLYSIS Glucose (6 carbons) PGAL (3 carbons) 1 Pyruvic Acid (3 carbons) Lose a “H” = 2 “H” + 2NAD  2NADH Use 2 ATP Make 4 ATP 2 3

SO, WHAT’S NEXT? If oxygen is not present  Fermentation If oxygen is present  Krebs Cycle

Cellular Respiration AnaerobicGlycolysisFermentationAerobicGlycolysisKrebs Cycle Electron Transport Chain Without Oxygen With Oxygen

FERMENTATION Location : Cytoplasm of the Cell Begins with the Pyruvic Acid from Glycolysis Purpose : Recycle NAD so glycolysis can continue  No additional ATP is made during fermentation. 2 Types :  Lactic Acid Fermentation  Alcohol Fermentation

LACTIC ACID FERMENTATION Summary:  Pyruvic acid + NADH  lactic acid + NAD (goes back to glycolysis) What types of organisms can do this?  Humans produce lactic acid in muscle tissue during rapid exercise when tissues can not get enough oxygen.

ALCOHOL FERMENTATION Summary  Pyruvic acid + NADH  alcohol + CO 2 + NAD (goes back to glycolysis) What types of organisms can do this?  Yeast!  Humans use alcohol made by yeast to make wine & beer and the carbon dioxide to make bread rise!

ATP TOTALS How many ATP does Anaerobic Respiration make?  Glycolysis  2 ATP  Fermentation  0 ATP  In total = 2 ATP

Cellular Respiration AnaerobicGlycolysisFermentationAerobicGlycolysisKrebs Cycle Electron Transport Chain Without Oxygen With Oxygen

AEROBIC RESPIRATION OCCURS IN THE MITOCHONDRIA Parts of the Mitochondria  Outer Membrane  Inner Membrane  Matrix  Fluid inside the mitochondria  Cristae  Inner folds of the mitochondria

KREBS CYCLE Location : Mitochondria (Matrix) Summary : 2  Occurs Twice since we made 2 pyruvic acids from Glycolysis.  Pyruvic Acid is broken down into CO 2.  More NADH is made.  FADH 2 is also made.  One ATP is made per cycle.

ATP TOTALS How many ATP does Aerobic Respiration make?  Glycolysis  2 ATP  Krebs Cycle  1 ATP but Happens Twice = 2 ATP  In total so far = 4 ATP o But we still have the Electron Transport Chain!

ELECTRON TRANSPORT CHAIN Location : Mitochondria (Inner Membrane) Summary : 32 ATP  Makes 32 ATP  Oxygen is needed!  Uses hydrogens from NADH & FADH 2.  NADH  NAD  FADH 2  FAD  The NAD & FAD then go back to glycolysis & Krebs cycle to pick up more “H’s”  At the end, oxygen combines with hydrogens to make water (H 2 O) !!

ATP TOTALS How many ATP does Aerobic Respiration make?  Glycolysis  2 ATP  Krebs Cycle  1 ATP but Happens Twice = 2 ATP  Electron Transport Chain  32 ATP  In total = 36 ATP!!!

REMEMBER: WHAT IS CELL RESPIRATION? A Process of breaking down food (sugar – glucose) in our cells to release energy (ATP) in order to use it to do work. Main Goal  Make ATP Did we do this?