Respiration
Converting and using energy
Respiration
Photosynthesis Review
► Photosynthesis
stored
energy in the form of
glucose.
 Glucose is what animals
and plants use as their
source of energy.
► But
ATP is the usable
energy in a cell…not
glucose. So…
Respiration: What is it?
► Essentially
cellular respiration breaks
food particles (glucose) down into ATP.
• ATP is the form of energy that cells can
use.
• Respiration provides all living things with
the energy they need.
• This is aerobic respiration, which requires
oxygen.
Respiration: What is it?
Respiration: Who does it?
► All
living things do
cellular respiration
…including plants.
Respiration: Where does it happen?
► Mitochondria
of a cell
 The “powerhouse” of the cell
 Found in plants and animals
Respiration: How does is happen?
3 steps of respiration:
Glycolysis:
 Glucose broken down into smaller parts
(2 molecules of Pyruvic Acid)
 ATP produced
2. Citric Acid Cycle (Krebs Cycle):
 Pyruvic Acid is broken down into CO2
 More ATP is produced.
1.
Respiration: How does is happen?
3 steps of respiration:
3.
Electron Transport Chain (ETC):
• Hydrogen is released
and forms with oxygen
to create water.
• More ATP is
produced
Respiration: How does is happen?
Therefore the overall reaction of
cellular respiration is the reverse of
photosynthesis:
glucose + oxygen  CO2 + water
respiration
photosynthesis
So what’s the moral of the
photosynthesis – respiration story??
ITS ALL ONE BIG CYCLE!!
NO TREES MEANS NO BREATHE
Check your understanding
1.
How is respiration different than photosynthesis,
how are they the same?
2.
What is the definition of respiration?
3.
Through what 3 steps does respiration produce
ATP?
The cell of an organism that starved to death is
tested and found to have a high concentration of
pyruvic acid. What failed?
4.
Anaerobic respiration
► Often
referred to as fermentation
► Does not require oxygen (O2)
• Byproduct is alcohol
• Only happens in oxygen deprived environments
- We had anaerobic respiration in our yeast lab!
- Brewing
• Does not produce as much ATP as aerobic
respiration, therefore plants and animals use
aerobic respiration whenever they can.