Fermentation 101
-
Upload
prunella-ronny -
Category
Documents
-
view
17 -
download
0
description
Transcript of Fermentation 101
Fermentation 101Fermentation 101
Ms. LevensailorMs. Levensailor
Cellular Respiration ReviewCellular Respiration Review
Oxidation: refers to the loss of electrons to Oxidation: refers to the loss of electrons to any electron acceptor (not just oxygen).any electron acceptor (not just oxygen).
For example: GlycolysisFor example: Glycolysis Oxidizes glucose to 2 molecules of pyruvate.Oxidizes glucose to 2 molecules of pyruvate. Oxidizing agent of glycolysis is NADOxidizing agent of glycolysis is NAD++ (not (not
oxygen).oxygen). Energy made is 2 ATPs (net) by substrate Energy made is 2 ATPs (net) by substrate
phosphorylation.phosphorylation.
Cellular Respiration ReviewCellular Respiration Review
If oxygen is present . . .If oxygen is present . . . Additional ATP is made by oxidative Additional ATP is made by oxidative
phosphorylation.phosphorylation.
HOWEVER, Glycolysis generates 2 ATPs HOWEVER, Glycolysis generates 2 ATPs whether oxygen is present or not!whether oxygen is present or not!
Anaerobic CatabolismAnaerobic Catabolism
Fermentation = anaerobic catabolism of Fermentation = anaerobic catabolism of organic nutrients.organic nutrients. Extension of glycolysis that can generate ATP Extension of glycolysis that can generate ATP
using only substrate-level phosphorylation.using only substrate-level phosphorylation. Requires sufficient supply of NADRequires sufficient supply of NAD++ to accept to accept
electrons during oxidation step of glycolysis.electrons during oxidation step of glycolysis. Without a mechanism to recycle NAD Without a mechanism to recycle NAD ++ from from
NADH, glycolysis would deplete the cell’s pool NADH, glycolysis would deplete the cell’s pool of NAD of NAD ++..
Anaerobic CatabolismAnaerobic Catabolism
How is NADHow is NAD++ recycled in aerobic recycled in aerobic conditions?conditions?The anaerobic alternative is to transfer The anaerobic alternative is to transfer electrons from NADH to pyruvate.electrons from NADH to pyruvate.There are many types of fermentation, There are many types of fermentation, differing in the waste products formed from differing in the waste products formed from pyruvate.pyruvate. Alcohol fermentationAlcohol fermentation Lactic Acid fermentationLactic Acid fermentation
Alcohol FermentationAlcohol Fermentation
Pyruvate is converted to ethanol (ethyl Pyruvate is converted to ethanol (ethyl alcohol) in 2 steps.alcohol) in 2 steps. 1. carbon dioxide is released from pyruvate, 1. carbon dioxide is released from pyruvate,
which is converted to acetaldehyde.which is converted to acetaldehyde. 2. acetaldehyde is reduced by NADH to 2. acetaldehyde is reduced by NADH to
ethanol.ethanol.Regenerating a a supply of NADRegenerating a a supply of NAD++
Alcohol fermentation by yeast (a fungus) is Alcohol fermentation by yeast (a fungus) is used in brewing & winemaking.used in brewing & winemaking.
Alcohol FermentationAlcohol Fermentation
Lactic Acid FermentationLactic Acid Fermentation
Pyruvate is reduced directly by NADH to form Pyruvate is reduced directly by NADH to form lactate (no release of COlactate (no release of CO22).).
Lactic acid fermentation by certain fungi and Lactic acid fermentation by certain fungi and bacteria are used in the dairy industry to make:bacteria are used in the dairy industry to make: CheeseCheese YogurtYogurt
Human muscles make ATP by lactic acid Human muscles make ATP by lactic acid fermentation.fermentation. Sugar catabolism for ATP production outpaces the Sugar catabolism for ATP production outpaces the
muscle’s supply of oxygen from the blood.muscle’s supply of oxygen from the blood.
Lactic Acid FermentationLactic Acid Fermentation
Check for UnderstandingCheck for Understanding
In your composition book:In your composition book: Make a Venn Diagram Make a Venn Diagram Compare and contrast Fermentation & Compare and contrast Fermentation &
Cellular RespirationCellular Respiration
Fermentation Cellular Respiration