Photosynthesis and Cell Respira on
Unit 5 : Fact Sheet
Photosynthesis and cellular respiration are connected
through an important relationship. The products of one
process are the reactants of the other. Notice that the
equation for cellular respiration is the direct opposite
of photosynthesis:
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Cellular Respiration: C6H12O6 + 6O2 → 6CO2 + 6H2O
Photosynthesis: 6CO2 + 6H2O → C6H12O6+ 6O2
Photosynthesis makes the glucose that is used in cellular respiration to make ATP. The glucose is then turned back into
carbon dioxide, which is used in photosynthesis. While water is broken down to form oxygen during photosynthesis, in cellular
respiration oxygen is combined with hydrogen to form water.
The Carbon cycle on earth is
driven by photosynthesis and cell
respiration. The trees take in
carbon dioxide and release
oxygen. As we continue with
deforestation we lesson the
effectiveness of this cycle. We are
also increasing the amount of
combustion based fuel sources
which release carbon dioxide into
the atmosphere. All of this thought
Photosynthesis
Photosynthesis is
the process by
which plants make
their own food
(autotrophs!)
“Photo” means Light
“Synthesis” means putting together
6CO2 + 6H2O → C6H12O6+ 6O2
Photosynthesis takes place in the
leaves of plants. The leaves are
made up of very small cells. Inside
these cells are tiny structures called
chloroplasts. Each chloroplast contains a green chemical called
chlorophyll which gives leaves their green color.
Cell Respiration
C6H12O6 + 6O2 → 6CO2 + 6H2O
Cellular Respiration, process in
which cells produce the energy
they need to survive. In cellular
respiration cells break down
glucose and store its energy in
molecules of adenosine triphosphate (ATP).
Reactants
Energy Yield
Byproducts
Aerobic
Glucose and Oxygen
High (~36-38 ATP)
CO2 and H2O
Anaerobic
Glucose
Low (~2ATP)
Animals - Lactic Acid
Yeast and Bacteria - Ethanol (wine) and CO2 (bread)