Aerobic vs. Anaerobic respiration

Objectives: Review the two types of anaerobic respiration. Explain the specific steps of alcohol & lactic acid fermentation. Compare & contrast aerobic & anaerobic respiration.

Aerobic respiration requires oxygen. Oxygen present

Alcohol fermentation converts pyruvate into ethyl alcohol. Glucose NAD+ 2 ATP 2 Pyruvate NADH e CO2 NAD+ C 2 Ethyl alcohol

Yeast use alcohol fermentation to break down glucose when oxygen is absent. Produces CO2 and alcohol Live yeast: undergoing anaerobic fermentation Breaking down glucose to form 2ATP Dead yeast: cannot undergo anaerobic fermentation Proteins necessary for reaction broken down due to change in temperature. Enzymes (proteins) only work at specific temperatures!

Alcohol fermentation is used to make wine, beer, & bread. CO2 helps bread rise Alcohol production for wine & beer

Glycolysis does not require oxygen. Glucose NAD+ 2 ATP 2 Pyruvate NADH When O2 continues on with cellular respiration to be converted into Acetyl CoA

When oxygen is absent, anaerobic respiration occurs. Two types: Alcohol fermentation Lactic acid fermentation Both utilize glycolysis to produce ATP Make very little ATP, 2 per glucose

Lactic acid fermentation turns pyruvate into lactic acid. Glucose NAD+ 2 ATP 2 Pyruvate NADH e NAD+ 2 Lactic acid

Lactic acid fermentation causes muscles to burn during exercise. When exercise too much or too quickly muscles use lactic acid fermentation. Build up of acid causes muscles to burn. Occurs in animals

Similarities & differences between anaerobic aerobic respiration. Uses glycolysis to produce ATP Produces 2 ATP per glucose Does not require oxygen Occurs in prokaryotes Uses glycolysis, Kreb cycle, & electron transport chain to produce ATP Produces 32-38 ATP per glucose Requires oxygen Occurs in eukaryotes

Key points Anaerobic respiration can be used when oxygen isn’t available to allow production of ATP. Anaerobic respiration has many commercial applications. Aerobic respiration is more efficient at producing ATP but its requires oxygen.