Upload
iliana-schmidt
View
22
Download
0
Tags:
Embed Size (px)
DESCRIPTION
QOD – What is the fuel of the cell called?. Making ATP from Glucose. 9.3. Cellular Respiration. Cellular Respiration - is the process by which mitochondria break down food molecules to produce ATP. Three Phases: Glycolysis, citric acid cycle, and ETC. Glycolysis. - PowerPoint PPT Presentation
Citation preview
QOD – What is the fuel of the cell called?
9.3
Cellular Respiration - is the process by which mitochondria break down food molecules to produce ATP.
Three Phases:
Glycolysis, citric acid cycle, and ETC
Glycolysis is a series of chemical reactions in cytoplasm of a cell that break down glucose (6 carbon) into 2 molecules of pyruvic acid (3 carbon)
Requires 2 molecules of ATP to start glycolysis
Breaking down of glucose into pyruvic acid produces 4 ATP and 2 NADH and 2H+
Anaerobic stage - doesn’t require oxygen
Glucose
2 ATP 2 ADP
c
P2
2 NAD + 2 NADH + 2H + 4 ATP 4 ADP
2 Pyruvates
2 ATP – Needed to start Glycolysis 2 NADH Produced 4 ATP Produced
Net Totals: 2 NADH 2 ATP
NAD+ is an electron carrier
Created during glycolysis when Glucose is broken down into pyruvic acid
Two energized electrons are added to NAD+ to create NADH and H+
Glycolysis Movie
The two molecules of pyruvic acid enter the mitochondria
They undergo a series of reactions before moving on to the second stage, citric acid cycle
Pyruvic acid is changed in a series of reactions Releases CO2
Joins with Coenzyme A
End result is acetyl-CoA (2 Carbon) Produces one NADH and H+
NAD+ NADH + H+
CO2
Also called the Krebs Cycle
Aerobic reaction - needs oxygen to occur
Is a series of chemical reactions (similar to the Calvin Cycle) in which the molecule used in the first reaction is the end product.
End result for 1 cycle:
1 ATP
3 NADH
1 FADH2
3 H+
The electron carrier molecules NADH and FADH2 take the energized electrons to the ETC
Found in the inner membrane of the mitochondria
1. Acetyl-CoA enters the Krebs Cycle and combines with the oxaloacetic acid (4carbon) to form citric acid (6 carbon)
2. Citric acid (6 carbon) releases a carbon to form CO2 and in the process creates NADH and H+. End result is a 5 carbon structure.
3. A second CO2 is produced when the 5 carbon structure releases a carbon and in the process ATP and NADH and H+ are produced. End result is a 4 carbon structure.
4. The 4 carbon structure goes through a series of reactions to reform oxaloacetic acid to ensure the cycle is able to continue.
5. 1st reaction - produces a FADH2
6. 2nd reaction - no byproducts
7. 3rd reaction - NADH and H+ form
8. Formation of Oxaloacetic acid
Video
Location: inner membrane of Mitochondria NADH and FADH2 take the energized
electrons to the ETC Electrons are passed from protein to
protein in the ETC slowly releasing their energy in steps Some can be used to form ATP
Some can be used by an enzyme to pump H+ ions into the center of the mitochondria
Aerobic reaction - requires oxygen to occur
The inner membrane becomes positively charged
The exterior membrane becomes negatively charged
Which attracts H+ ions(because they are positive)
The gradient of H+ ions created provides the energy needed to create ATP
The final electron acceptor is oxygen which forms 2 waters, when oxygen reactions with four H+ and 4 electrons (lost their energy)
Why we need oxygen, otherwise we would have a build up of electrons, until the ETC could no longer accept anymore electrons and would no longer function
Overall the ETC produces
32 ATP
Water
NAD+
FAD+
ETC in cellular respiration
Cellular Respiration creates
36 ATP
6 NADH
1 FADH2
3 CO2
H2O
6 H+
An anaerobic process that occurs in the absence of oxygen for short periods of time that allows ATP to be created until oxygen can be restored
During heavy exercise
Two major types
Lactic Acid Fermentation
Alcoholic Fermentation
Lactic Acid Alcoholic Cellular Respiration
Glucose Glucose Glucose
Glycolysis Glycolysis Glycolysis
CO2 CO2
Lactic acid alcohol Carbon dioxide + water
2 ATP 1 ATP 36 ATP
Process that supplies energy when oxygen is limited
Without oxygen the ETC begins to back up and it can no longer accept electrons
Therefore there is no NAD+ or FAD+ to supply to the citric acid cycle or glycolysis
NAD+ can still be created without oxygen but FAD+ can not
Two molecules of pyruvic acid use NADH to form 2 molecules of lactic acid
This release NAD+ which can be used in glycolysis allowing 2 ATP
During extreme exercise muscle cells produce lactic acid, but after it is used to create NAD+ it travels to the liver to be turned back into pyruvic acid
Lactic acid build up in the muscle cells causes muscle fatigue and soreness
Alcoholic fermentation is used by yeast and some bacteria cells to produce CO2 and ethyl alcohol.
Yeast - used to make bread rise by releasing CO2. The heat from baking does kill the yeast.
Bacteria - used to create alcohol from fruits and plants
Similarities
Both use ETC
Both use cycles of chemical reactions to form ATP
Both create a concentration gradient of H+ by using a Hrydrogen ion pump
Both utilize PGAL
Differences:
Cellular Res.
Produces ATP
Gives off CO2
Doesn’t require light
Occurs in plants and animals
Energy carrier NADH and FADH2
Photosynthesis
Produces Glucose
Requires light
Gives off oxygen
Occurs only in plants or cells with chlorophyll
Energy carrier NADPH