ETC occurs here
Krebs Cycle
Occurs here
Cellular Respiration:
• A series of BIOCHEMICAL PATHWAYS… the
product of 1 reaction is the reactant of the next
reaction
• Occurs in the mitochondria ( & cytoplasm)
• Is the process of creating ENERGY…ATP!!!!
• food broken down into organic molecules,
ultimately broken down into GLUCOSE
– glucose changed into/converted into ATP
(ENERGY)
• enzyme controlled
CR
•
•
Occurs in BOTH PLANTS AND ANIMALS
Has 3 stages:
1. Glycolysis – anaerobic: w/o Oxygen
2. Krebs Cycle (aka: Citric acid cycle) –
aerobic: require oxygen
3. Electron Transport Chain (ETC) aerobic
Glycolysis:
• Occurs in the cytoplasm (cytosol)
• Chemical RXN where sugarGLUCOSE is broken down into
2 Pyruvic Acid molecules
• Produces 2 ATP molecules for every
1 glucose molecule
• NAD provides energy for the change
(an e- energy carrier)
Section 9-1
Glucose
2 Pyruvic acid
To the electron
transport chain
Go to
Section:
Products from Glycolysis move
into the Mitochondria
THE PRODUCT (Pyruvic Acid) WILL
THEN BE USED AS THE REACTANT IN
THE NEXT REACTION
Hence…Biochemical Pathway
CK ?? Topic CR
Date: 10-11-10
1. What is the purpose of
Cellular Respiration?
2. Where are the 2 places does
CR occurs?
3. What are the 3 stages of CR?
CK ?? Topic CR
Date: 10-11-10
4. How many usable ATP result from
Glycolysis?
5. What is the second stage of CR?
6. Where does the second stage take
place?
7. What does the term aerobic
mean?
Stage 2
Krebs (Citric Acid Cycle):
• Oxygen is required – Aerobic Respiration
• A series of chemical rxns… a cycle
– Pyruvic Acid is further broken down:
• into Acetyl CoA
• CO2 is produced and
• released into the air from animal cells
• Or in plants move to the chloroplasts to be
used for photosynthesis
Pyruvic Acid is further broken
down:
• 2 ATP are produced and
• NADH & FADH are produced (high
energy electron carriers) which will
provide the energy to bond the last
phosphate in ADP to create ATP!
ENERGY
Citric Acid Cycle:
• Takes place in
the matrix of
the mitochondria
In summary:
Pyruvic Acid is
further broken
down into
Acetyl CoA as
it enters the
Krebs Cycle
Stage 3Electron Transport Chain:
Stage 3Electron Transport Chain:
• Occurs in the inner Mitochondrial
Membrane
• Majority of the ATP (34 ATP) are produced
during ETC
• The high-energy electrons produced
during the Krebs Cycle (NADH and
FADH2) are used to convert ADP into ATP
Chemical Formula Cellular
Respiration:
Sugar + Oxygen  Energy + Carbon Dioxide + Water
C6H12O6 + 6O2 36 ATP + 6CO2 + 6H2O
Glycolysis:
• Goal: To break down sugar into 2 Pyruvic
Acids
• Who: Both plant and animals
• Where: In the cytoplasm of the cell
• Products: 2ATP, 2NADH, 2 Pyruvic
Krebs cycle:
• Goal: convert (change) the pyruvic acid
into NADH and FADH2
• Where: mitochondria
• Products: Energy carriers: NADH &
FADH2, CO2 (released to environment)
and 2 ATP
Electron Transport Chain
(chemiosmosis making ATP!!)
• Goal: break down NADH and FADH2
to produce ATP
• Where: Mitochondria membrane
• Products: 32 -34 ATP
AS A RESULT OF AEROBIC
CELLULAR RESPIRATION:
•
•
•
•
2 ATP FROM GLYCOLYSIS
2 ATP FROM KREBS CYCLE
32-34 ATP FROM THE ETC
TOTAL OF:
– 36-38 ATP FOR EVERY MOLECULE OF
GLUCOSE
IF NO OXYGEN IS AVAILABLE…
• Anaerobic Respiration (FERMENTATION):
– Begins with Glycolysis
– DOES NOT REQUIRE OXYGEN
• Also known as FERMENTATION
2 types of FERMENTATION
1. Alcoholic fermentation
2. Lactic acid fermentation
Lactic Acid Fermentation:
• Pyruvic acid converted
(changed) into lactic acid
• Used to make cheese, yogurt,
and is the stuff that
accumulates in muscles (sore)
• 2 ATP only
Alcoholic Fermentation:
• Used to make beer, wine
• Yeast used in process
• 2 ATP only
Reproduce
Through
BUDDING!!
Clearly Not as
efficient as
aerobic
respiration
•Photosynthesis and
cellular respiration
are opposite rxns.
Photosynthesis & CR
are opposite rxns.
Photosynthesis :
• removes Carbon Dioxide from the
atmosphere and puts back oxygen.
Cellular Respiration:
• Removes oxygen from the atmosphere
and puts back carbon dioxide.