anaerobic cellular respiration. aerobic… what? we have reviewed aerobic respiration this is the...
TRANSCRIPT
Anaerobic Cellular Respiration
Aerobic… What?
• We have reviewed aerobic respiration
• This is the process of taking molecules of glucose and breaking them down using oxygen from the environment
• It provides a huge amount of energy to a cell that can do it
Aerobic… What?
• This process makes roughly 32 ATP (remember that number is not set in stone)
• It also creates H2O and CO2
• Remember it can only be done by some organisms
Intro to Anaerobic Respiration
• When no oxygen is present or when a cell does not have mitochondria a different pathway is used after glycolysis
• After pyruvate is formed, the cells undergo fermentation
• Fermentation is the process of harvesting chemical energy without using oxygen
Intro to Anaerobic Respiration
• Fermentation does not actually increase the amount of ATP that the cell receives
• We have the 2 net ATP from glycolysis… and that’s it
• Fermentation only produces NAD+ so glycolysis can continue
• This means that fermentation produces no ATP, it just helps keep glycolysis running
Intro to Anaerobic Respiration
• Different types of organisms perform anaerobic respiration
• Obligate anaerobic organisms must have anaerobic conditions– Aerobic conditions will kill
them
• Facultative anaerobic organisms can have aerobic or anaerobic conditions
Lactic Acid Fermentation
• There are two main types of fermentation
• Lactic acid fermentation is the process of turning the pyruvate into lactate (an ionized form of lactic acid)
• Lactic acid fermentation happens in animal muscle cells and some bacteria
Lactic Acid Fermentation
• There are two main types of fermentation
• Lactic acid fermentation is the process of turning the pyruvate into lactate (an ionized form of lactic acid)
• Lactic acid fermentation happens in animal muscle cells and some bacteria
Lactic Acid Fermentation
• In lactic acid fermentation involves oxidizing NADH into NAD+ and converting what is left of the pyruvate into lactate
• The NAD+ is sent back to glycolysis to reload glycolysis with NAD+ that it needs to continue
Alcoholic Fermentation• Alcoholic fermentation
happens in fungi, some bacteria plant cells
• Yeast is the most common organism that does this
• It changes pyruvic acid to ethyl alcohol
• It also causes the loss of one molecule of CO2 and the gain of one NAD+
Alcoholic Fermentation
• Lactic acid fermentation takes pyruvate and converts it to a 2 carbon molecule known as ethanol
• This process oxidizes NADH into NAD+ and releases CO2 into the environment
Alcoholic Fermentation
• Alcoholic fermentation has been used by humans for hundreds of years
• This process gives us bread, cheeses, yogurts and alcohols
Video
• https://www.youtube.com/watch?v=FttkHVBu2IA
Other Macromolecules?
• Ok, we have broken down glucose…
• However other things can be broken down for energy
• Complex carbohydrates can be broken down into monosaccharides and given the same process
Other Macromolecules?
• Fats contain a high number of hydrogens
• This means they can easily be broken down in order to power oxidative phosphorylation
• Remember how fats contain 9kc/gram of energy
Other Macromolecules?
• Proteins can be used for fuel as well
• You body often will go through carbohydrates and fats first because they are easier to break down
• In order to be used, proteins must first be broken down to individual amino acids
Side By Side ComparisonType of Molecule Produced Lactic Acid
FermentationAlcoholic
FermentationAerobic Respiration
ATP 2 32
CO2 0 2 6
H2O 0 6