Cellular Respiration
Converting Chemical Energy from Carbohydrates
into Chemical Energy of ATP
Cellular Respiration (Aerobic )
• How do cells transform
matter and energy?
• What are the major
inputs and outputs of cell
respiration?
• What is the relationship
between cell respiration
and study
photosynthesis?
Cellular Respiration and Photosynthesis
•
These are ‘opposite’
processes
•
The products of
photosynthesis are the
reactants of respiration
and vice versa.
•
Energy stored through
photosynthesis is
released through
cellular respiration
Cellular Respiration and Photosynthesis
•
Photosynthesis stores
small packets of energy in
a larger packet.
 Like turning in one
hundred $1 bills to get a
$100 bill
•
Cell Respiration takes a lot
of energy and breaks it into
smaller packets.
 Like turning in a $100
bill and getting five $20
bills.
Cellular Respiration Overview
In the mitochondria of living things, oxygen helps the
break- down of sugars (glucose) to release energy
useable by the cell (ATP)
Products and Reactants
(1) C6H12O6 + (6) O2
(6) CO2 + (6) H2O + ATP
Cellular Respiration Overview
• Glycolysis is the anaerobic process of breaking down
glucose to generate ATP
• Krebs Cycle and Electron Transport require oxygen to
further break down carbon molecules to generate ATP
O2
Pyruvic acid
Mitochondria
Glucose
H+
Glycolysis
2
Krebs
Cycle
CO2
36
Electron
Transport
Chain
H 2O
Glycolysis
•
Glucose (6 carbon
sugar) breaks down
into pyruvate (3
carbon molecules )
and ATP (energy)
•
Similar to reversing
the final stage of
photosynthesis when
two 3-carbon sugars
were used to make
glucose
Krebs Cycle
•
Pyruvate (3
carbon) breaks
down into
carbon dioxide
(1 carbon) and
electrons are
used to
generate ATP
(energy)
•
Similar - in
reverse - to the
Calvin cycle in
photosynthesis
Electron Transport Chain
Electron Transport Chain
•
Electrons generated during glycolysis
and Kreb’s cycle are used to generate
ATP
•
At the end they come together with
oxygen to form water
•
Again, similar, but in reverse of the
electron transport chain in the light
dependent reactions of photosynthesis
Energy Transformed - Cell Respiration
•
36 ATP units are released from one glucose unit
•
A unit of glucose molecules contains 686 kcal of stored
energy. A unit of ATP stores 7.5 kcal.
•
How efficient is the transformation from energy stored in
glucose to energy released as ATP?