Bellringer 3/30
• What is the purpose of photosynthesis?
• What does the plant need to perform
photosynthesis?
• What are the products of photosynthesis?
• What is the purpose of respiration?
• What does an organism need to perform cellular
respiration?
• What are the products of cellular respiration?
• What are the products of alcoholic
fermentation?
Why do organisms need food?
Organisms use food to make
ATP
ATP (adenosine triphosphate) → the molecule
used for energy in ALL cells.
• When a cell needs to use energy, it
breaks off one phosphate group to
make ADP
release energy = ATP → ADP + P
• When a cell wants to store energy, it
makes ATP
store energy = ADP + P → ATP
What process makes ATP (energy)?
RESPIRATION!
• Chemical reaction that makes ATP for ALL
organisms.
TWO types of respiration…
Aerobic
(Cellular) OR
Respiration
Anaerobic
Respiration
(Fermentation)
Aerobic (Cellular) Respiration
Uses O2 and
food (glucose) to
make ATP
All organisms
except some
fungi and
bacteria
Occurs in the
MITOCHONDRIA
Produces H2O
Makes LOTS of
ATP
and CO2
Carbon Dioxide
Excreted out
Energy
Water
Cell
Used by cell
Oxygen
Glucose
Need to get it from outside
cell
Get from food
The PRODUCTS of one reaction are the REACTANTS of
the other reaction.
In which way are photosynthesis and cellular
respiration different?
A. Cellular respiration stores ATP, while
photosynthesis releases ATP.
B. Cellular respiration produces oxygen, while
photosynthesis uses oxygen.
C. Photosynthesis releases energy, while cellular
respiration stores energy.
D. Photosynthesis uses carbon dioxide, while
cellular respiration produces carbon dioxide.
Anaerobic Respiration (Fermentation)
• Does NOT use Oxygen
• Uses ONLY food (glucose) to make ATP
• makes very little ATP
Fermentation (anaerobic respiration)
can be…
LACTIC ACID
• Occurs in humans when
there is a lack of O2
▫ Result of pushing yourself
beyond your usual
endurance
• Produces lactic acid =
muscle cramps
ALCOHOLIC
• Occurs in yeast
• Produces CO2 and
ethyl alcohol
Which organism is most likely to use anaerobic
respiration?
A.
B.
C.
D.
Bird
Moss
Tree
Yeast
Two different species of bacteria are examined.
Scientists find that Species X always produces CO2
and H2O during cellular respiration. Species Y
always produces ethyl alcohol and CO2. Which
conclusion can be made from these observations?
A.
B.
C.
D.
Only Species Y is aerobic
Only Species Y is anaerobic
Both Species X and Y are aerobic
Both Species X and Y are anaerobic.
Bioenergetic Reactions
Photosynthesis
CO2 + H2O → C6H12O6 + O2
Carbon dioxide + water →
glucose
+ oxygen
Aerobic Respiration
C6H12O6 + O2 → CO2 + H2O
Glucose
+ 36 ATP
+ oxygen → carbon dioxide + water
Anaerobic Respiration (Alcoholic Fermentation)
C6H12O6 → CO2 + C2H5OH
glucose
→
+ 2 ATP
carbon dioxide + ethyl alcohol