Cellular Respiration
The Big Picture
Glycolysis
Krebs Cycle
Electron Transport Chain
7.1 Glycolysis and Fermentation
If I have a $10.00 bill and a $10.00 check, which is better?
ATP is like cash in the cell
Glucose, NADH, FADH2 are like checks in a cell. They have to be converted
in order to use for energy.
What happens when you breathe on a window? What two things are
released? Water and Carbon Dioxide
These are byproducts of Cellular Respiration
Write down the equation for photosynthesis and cellular respiration. Compare
6CO2 + 6H20 +energy--- C6H1206 +6O2
C6H1206 +6O2 - 6CO2 + 6H20 + ATP
Cellular Respiration
Cellular Respiration and Photosynthesis are not the reverse
of each other. The products of photosynthesis are the
starting point of cellular respiration.
1st Law of Thermodynamics: energy is neither created nor
destroyed
Photosynthesis= 686 Kcal of energy in one mole of glucose
Cell. Respiration releases 686 Kcal from one mole of glucose
Cellular Respiration is the process by which cells make ATP
by breaking down organic compounds
There are TWO stages:
Glycolysis and Aerobic Respiration
Overview of Aerobic Respiration
Glycolysis
Krebs Cycle
Glycolysis
1 molecule of glucose is converted into 2- 3carbon molecules of Pyruvic Acid
and a small amount of ATP and NADH
If Oxygen is present, Pyruvic Acid is broken down and NADH makes a large
amount of ATP. This is Aerobic Respiration.
If no oxygen is present, Pyruvic acid can go through anaerobic pathways called
Fermentation.
Fermentation
Many cultures depend on fermentation for their diets.
Examples?
If oxygen is not present, Pyruvic Acid goes along another
pathway. It does not produce ATP, but other organic
molecules that regenerates NAD+ to keep the cycle
going.
In Lactic Acid Fermentation, it converts to lactic acid.
In Alcoholic Fermentation, it converts to ethyl alcohol and
carbon dioxide.
Electron Transport Chain
NADH + H+ + 3 ADP + 3 Pi + 1/2 O2 → NAD+ + H2O + 3 ATP
The electron transport chain allows the release of
the large
amount
of chemical
energy
in + 2 ATP
FADH2
+ 2 ADP
+ 2 Pi
+ 1/2 O2 →
FAD+stored
+ H2O
reduced NAD+ (NADH) and reduced FAD
(FADH2). The energy released is captured in the
form of ATP (3 ATP per NADH and 2 ATP per
FADH2).
Energy Total:
Source
Number ATP
Produced
To Start Glycolysis
-2 ATP
Glycolysis
4 ATP
Movement into Matrix
-2 ATP
Krebs Cycle (ATP & GTP)
2 ATP
Electron Transport (NADH & FADH2)
34 ATP
NET TOTAL
36 ATP
NADH= 3 ATP
FADH2= 2 ATP
• http://www.biology.clc.uc.edu/courses/bio1
04/cellresp.htm
ATP YIELD
• Total
yield
of 38
ATP
• Varies
from
cell to
cell