respiration. respiration respiration the process by which food molecules are broken down –food...
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RespirationRespiration
RespirationRespiration
• Respiration the process by which food molecules are broken down– Food molecules are 6-carbons sugars – You take in food which is digested and broken
down into 6-carbon sugars– Plants can’t “eat” so they make 6-carbon
sugars with photosynthesis– Mitochondria then transform the “food energy”
into chemical energy
RespirationRespiration
• A 6-carbon sugar contains an enormous amount of energy (for a cell)
• Mitochondria “make change” energetically
• Take the energy in a sugar and convert it into more conveniently-sized packages
RespirationRespiration
C6H12O6 + 6O2 → 6CO2 + 6H2O + energyCarbondioxide
WaterCarbohydrate Oxygen
RespirationRespiration
• Aerobic respiration: processes that require oxygen in order to take place
• Anaerobic respiration: processes that do not require oxygen
Aerobic RespirationAerobic Respiration
• Step 1: Glycolysis
• Step 2: Breakdown of pyruvic acid
• Step 3: Citric acid cycle
• Step 4: Electron transport chain
RespirationRespiration
MATRIX:Breakdown ofpyruvic acid, Citric acid cycle
INNER MEMBRANE:Electron transportchain
Outer membrane
CYTOPLASM:Glycolysis
Step 1: GlycolysisStep 1: Glycolysis
• Occurs in cytoplasm
• Does not require oxygen
• Involves splitting a glucose (6-carbon sugar) into 2 3-carbon molecules: pyruvic acid
Step 1: GlycolysisStep 1: Glycolysis
• Also produces H+ ions and energizes electrons which are captured by NAD+, forming NADH + H+
Step 1: GlycolysisStep 1: Glycolysis
Glucose
Step 1: GlycolysisStep 1: Glycolysis
Glucose
2 ATP 2 ADP
Step 1: GlycolysisStep 1: Glycolysis
Glucose
2 ATP 2 ADP
P
P
2 PGAL
Step 1: GlycolysisStep 1: Glycolysis
Glucose
2 ATP 2 ADP
P
P
2 PGAL
4ADP + 4 Pi
2 NAD+ 2NADH + 2H+
4ATP
Step 1: GlycolysisStep 1: Glycolysis
Glucose
2 ATP 2 ADP
P
P
2 PGAL
4ADP + 4 Pi
2 NAD+ 2NADH + 2H+
4ATP
2 Pyruvicacid
Step 1: GlycolysisStep 1: Glycolysis
• Net yeild– 2 ATP (uses 2, produces 4)– 2 NADH– 2 pyruvic acid
Aerobic RespirationAerobic Respiration
Step 1: Glycolysis
• Step 2: Breakdown of pyruvic acid
• Step 3: Citric acid cycle
• Step 4: Electron transport chain
Step 2: Breakdown of Step 2: Breakdown of Pyruvic AcidPyruvic Acid
• Occurs when pyruvic acid (from glycolysis) enters the mitochondrial matrix
• Requires oxygen– If there is no oxygen present pyruvic acid
enters fermentation
Step 2: Breakdown of Step 2: Breakdown of Pyruvic AcidPyruvic Acid
• Involves breaking CO2 off pyruvic acid
• Remaining portion of pyruvic acid combines with coenzyme A to form acetyl-CoA
Step 2: Breakdown of Step 2: Breakdown of Pyruvic AcidPyruvic Acid
• Also produces H+ and energizes electrons which are captured by NAD+, to form NADH + H+
Step 2: Breakdown of Step 2: Breakdown of Pyruvic AcidPyruvic Acid
To citricacid cycle
Mitochondrialmembrane
“Exhaled”
Step 2: Breakdown of Step 2: Breakdown of Pyruvic AcidPyruvic Acid
• Net yeild– 2 NADH– Acetyl-CoA
Aerobic RespirationAerobic Respiration
Step 1: GlycolysisStep 2: Breakdown of pyruvic acid
• Step 3: Citric acid cycle
• Step 4: Electron transport chain
Step 3: Citric Acid CycleStep 3: Citric Acid Cycle
• Occurs in mitochondrial matrix
• Acetyl-CoA is transformed into citric acid through a series of reactions
Step 3: Citric Acid CycleStep 3: Citric Acid Cycle
• More ATP and CO2 are produced
• More H+ are produced and electrons are energized
• NAD+ and FAD capture them to form NADH + H+ and FADH
Step 3: Citric Acid CycleStep 3: Citric Acid Cycle
CITRICACID
CYCLE
4C
5C
6C – Citric acid
Step 3: Citric Acid CycleStep 3: Citric Acid Cycle
• Net yield– 2 ATP– 6 NADH
– 2 FADH2
Aerobic RespirationAerobic Respiration
Step 1: GlycolysisStep 2: Breakdown of pyruvic acidStep 3: Citric acid cycle
• Step 4: Electron transport chain
Step 4: Electron Transport ChainStep 4: Electron Transport Chain
• Happens on inner membrane of mitochondria
• Occurs only if oxygen is present– Oxygen is final electron acceptor– If no oxygen is present reaction stops
Step 4: Electron Transport ChainStep 4: Electron Transport Chain
• Electrons come from NADH and FADH molecules which gathered them during glycolysis and CTA
• Energy from electrons is used to add Pi to ADP, forming ATP
• At the end of the chain, oxygen accepts the electrons and combines with 2 H+ ions to form water
Step 4: Electron Transport ChainStep 4: Electron Transport Chain
Innermitochondrial
membrane
Outermitochondrial
membrane
Electron transport chain
CytochromesInter-
membranespace
Cytochromes
Step 4: Electron Transport ChainStep 4: Electron Transport Chain
• Net yeild– 32 ATP
Aerobic RespirationAerobic Respiration
• Step 1: Glycolysis
• Step 2: Breakdown of pyruvic acid
• Step 3: Citric acid cycle
• Step 4: Electron transport chain
Aerobic RespirationAerobic Respiration
Glycolysis 2 ATP
Citric acid cycle 2
Electron transport chain **32
ATP
ATP**Makes ATP from electrons carried to it from the first 3 steps
Aerobic RespirationAerobic Respiration
Makes 36 ATP
Anaerobic RespirationAnaerobic Respiration
• Pyruvic acid molecules are still formed through glycolysis
• Broken down differently:– No ATP is produced after glycolysis– NAD+ is regenerated so glycolysis can
continue
Anaerobic RespirationAnaerobic Respiration
• 2 types:– Lactic acid fermentation– Alcoholic fermentation
Lactic Acid FermentationLactic Acid Fermentation
• Lactic acid is end product
• Occurs when muscles require energy at a faster rate than it can be supplied through aerobic respiration
• Causes burning sensation in muscles
Lactic Acid FermentationLactic Acid Fermentation
GlycolysisGlycolysis
Lactic Acid FermentationLactic Acid Fermentation
Lactic Acid FermentationLactic Acid Fermentation
• Net yield– 2 ATP
Alcoholic FermentationAlcoholic Fermentation
• Ethyl alcohol and CO2 are end products
• Occurs in organisms that live in environments lacking oxygen
• Source of bubbles in beer and champagne and causes baking bread to rise
Alcoholic FermentationAlcoholic Fermentation
Glycolysis
Glycolysis
Alcoholic FermentationAlcoholic Fermentation
Glycolysis
2 Ethanol
2 CO2
Comparison of Aerobic Comparison of Aerobic Respriation and FermentationRespriation and Fermentation
• How many ATP does aerobic respiration produce?
• How many ATP does fermentation produce?
36 ATP 2 ATP
WE’RE DONE!!!!
Step 1: GlycolysisStep 1: Glycolysis
Glucose
2 ATP 2 ADP
P
P
2 PGAL
4ADP + 4 Pi
2 NAD+ 2 Pyruvicacid
Step 2: Breakdown of Step 2: Breakdown of Pyruvic AcidPyruvic Acid
To citricacid cycle
“Exhaled”
Step 3: Citric Acid CycleStep 3: Citric Acid Cycle
CITRICACID
CYCLE
4C
5C
6C – Citric acid
4C
Step 4: Electron Transport ChainStep 4: Electron Transport Chain
Innermitochondrial
membrane
Outermitochondrial
membrane
Electron transport chain
CytochromesInter-
membranespace
Cytochromes
Lactic Acid FermentationLactic Acid Fermentation
Glycolysis
Alcoholic FermentationAlcoholic Fermentation
Glycolysis
2 Ethanol
2 CO2