Download Lactic Acid fermentation

Overview of Respiration
C6H1206 + 6O2
6CO2 + 6H2O
• Organisms use stored energy in glucose
• 36 ATP per molecule of glucose is made
• 3 Parts: Glycolysis, Krebs Cycle, and Electron
transport
– Glycolysis is anaerobic – does not require oxygen
– Aerobic – requires oxygen
• Electron transport & Krebs cycle
Mitochondria
Glycolysis
• Glucose is broken down & converted into 2
molecules of pyruvate
– 4 molecules of ATP are produced but 2 are used
• 2 ATP and 2 NADPH are formed per each glucose
molecule broken down
– 4 molecules are produced but 2 are used
Krebs Cycle
• Glycolysis nets 2 ATP and 2 Pyruvate
• Energy is still contained in pyruvate
– Transported into mitochondria
• Pyruvate is broken down into CO2
– Krebs Cycle
– Tricarboxylic Acid Cycle (TCA)
– Citric Acid Cycle
Krebs Cycle
1. Pyruvate forms acetyl CoA (*before Krebs Cycle)
1. CO2 is released
2. Acetyl CoA forms citric acid
3. Citric Acid breaks down
1. Generates 1 ATP, 3 NADH, 1 FADH2
4. Acetyl CoA and citric acid are generated and
cycle continues
Krebs Cycle
• 2 pyruvate are formed during glycolysis
– Krebs cycle happens once per pyruvate
– Twice total
• Net Yield of Krebs cycle is 6 CO2, 2 ATP, 8
NADH, 2 FADH2
Aerobic Respiration
• Aerobic respiration – electron transport is last
step
• Most ATP is produced
• NADH and FADH2 are used to make ATP
Electron Transport
• Similar to photosynthesis
• NADH/FADH release electrons
• form NAD+ and FAD
• H+ ions are pumped across membrane and create
gradient
– Chemiosmosis occurs
– ATP Synthase pump creates ATP from ADP
• Net yield of electron transport: 32 ATP
Steps of Respiration
• Glycolysis - anaerobic
– Glucose is broken down into 2 pyruvate
– 4 ATP produced, 2 used, Net 2 ATP
• Krebs Cycle - aerobic
– Pyruvate becomes acetyl CoA via coenzyme A
– Acetyl CoA becomes citric acid
– Net Yield 6 CO2, 2 ATP, 8 NADH, 2 FADH2
• Electron Transport aerobic
• NADH, FADH2, supply electrons/protons for chemiosmosis
– ATP Synthase creates ATP
Anaerobic Respiration
• No oxygen present: ATP can continue to be
created through glycolysis
– Only 2 ATP produced
– Glycolysis stops when all NAD+ is used
• Fermentation – regenerates cell’s supply of
NAD+ and produces a small amount of ATP
2 Types of Fermentation
Lactic Acid fermentation
• Convert pyruvate to lactic acid
• Muscles produce lactic acid when not enough O2
• Muscles become fatigued and sore
• Produced by microorganisms
– Produce food such as yogurt, cheese, sour cream
Alcohol Fermentation
• Pyruvate is converted to ethyl alcohol and CO2
• Similar to lactic acid fermentation
Review of Photosynthesis
and respiration
Photosynthesis
Phase 1: Light-Dependent Reactions
• Require light
• Light energy breaks apart water
• Electron transport chain
– Chemiosmosis
– ATP synthase
• Produce ATP and NADPH
– needed to produce glucose in light-independent
reactions
Photosynthesis
Phase 2: Light-Independent Reactions
• Calvin Cycle
• Occur in light or dark conditions
• Change CO2 to glucose
*Alternative Cycles – environmental factors
Steps of Respirations
• Glycolysis
– Glucose is broken down into 2 pyruvate
– 4 ATP produced, 2 used, Net 2 ATP
• Krebs Cycle
– Pyruvate becomes acetyl CoA via coenzyme A
– Acetyl CoA becomes citric acid
– Net Yield 6 CO2, *2 ATP*, 8 NADH, 2 FADH2
• Electron Transport
– NADH, FADH2, supply electrons/protons for chemiosmosis
– ATP Synthase creates ATP – 32 ATP created