Download Cellular Respiration Notes

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TEXTBOOK READING PP. 340 - 346
Notes Cellular Respiration
C6H12O6
+
Glucose
o
o
o
6O2
Oxygen
6CO2
enzymes
+
Carbon Dioxide
6H2O + ATP
Water
Energy
occurs in the cells of all living organisms
it breaks down fuel (glucose) to yield energy required for cells to function
can occur with or without the oxygen
Aerobic respiration – cellular respiration that uses oxygen
There are three main stages in the process: glycolysis, Kreb’s cycle, and
the electron transport system.
First stage Glycolysis
(does not require oxygen)
o occurs in the cytoplasm
o 6-carbon glucose is split in half to make two molecules of 3-carbon pyruvate
o only 2 ATPs are produced
Second stage The Krebs Cycle
(occurs when oxygen is present)
o occurs in the mitochondria
o pyruvate is broken down to carbon dioxide which is released as a gas
o more ATP is made
Third stage Electron Transport System
o
o
o
o
o
o
occurs in the mitochondria’s inner membrane
requires oxygen
is a series of electron carrier molecules
electrons and hydrogen ions pass along electron carrier molecules
net 36 ATPs are produced
the electrons and hydrogen ions join with oxygen to form water
Anaerobic respiration – cellular respiration that occurs
when oxygen is low or absent
Glycolysis
o occurs in the cytoplasm
o 6-carbon glucose is split in half to make two molecules of 3-carbon pyruvate
o only 2 ATPs are produced
Fermentation
o pyruvate is converted to
- ethyl alcohol by yeast (how wine is produced)
- lactic acid in bacteria cells and muscle cells
ATP: The Fuel of Cells
ATP stores chemical energy in its structure
the energy first came from the sun and then stored in food
cellular respiration produces ATP
every cell requires large amounts of ATP each day to do its work
ATP provides the energy for biosynthesis, reactions that form larger molecules
- formation of starch from glucose
- building of proteins from amino acids
o example: energy stored in food is like stocks and ATP is like cash
o
o
o
o
o
ATP
Energy in
Energy out
ADP
+P