1. Photosynthesis and cellular respiration are opposing reactions. Photosynthesis uses carbon dioxide, water, and sunlight to produce glucose and oxygen, while cellular respiration breaks down glucose and oxygen to produce carbon dioxide and water. 2. Cellular respiration can occur aerobically, using oxygen to produce the most ATP, or anaerobically through fermentation when oxygen is absent. Glycolysis is the only process that occurs in both aerobic and anaerobic cellular respiration. 3. The electron transport chain produces the most ATP and requires oxygen, so it only occurs during aerobic cellular respiration. Glycolysis and fermentation occur in the cytoplasm, while the Krebs cycle and electron transport chain occur in the mitochondria

1. Cellular respiration
THE POWER OF ATP

2. Thermodynamics recap
• Energy is neither created nor destroyed, it only changes forms!
• Each transfer of energy leads to a little more being unusable!
Takeaway: Every time you eat and convert food energy to cellular
energy, some energy is lost as heat to the universe (increasing entropy)
• This allows our cells to remain organized

3. Photosynthesis recap
• How plants convert energy from the sun to food energy (glucose) in
chloroplasts
• Light-dependent reactions take place in the thylakoid
• Make the necessary ingredients for the light-independent reactions!
• Light-independent reactions take place in the stroma
• Make simple sugars like glucose!
CO2 + H2O  C6H12O6 + O2
sunlight
Carbon dioxide + water  glucose (sugar) + oxygen

4. thermodynamics
If energy is cycled
between producers and
other organisms, can
you make a prediction
on what the equation
for cellular respiration
would be?

5. Cellular respiration
• Photosynthesis is how plants make their own food (glucose).
• This is why they are called autotrophs!
• How do other organisms get their food?
• Consuming other organisms!
• Why do we even need food?
• Energy is needed to produce work. Work is
anything that an organism does! If we are even
just sitting or sleeping, an organism is doing
work.
• Our cells can’t use the food as it comes, it
must convert it into usable energy. Cellular
energy is ATP

6. ATP
• Adenosine Triphosphate
• Adenine (nitrogenous base)
• Ribose (sugar)
• 3 phosphate groups
• The phosphate groups are unstable
• Energy is stored in the bonds between phosphates
• The 2 end phosphates are easily broken off
• When the bonds are broken, energy is released
• ADP plus Pi is formed and this is recycled to produce more ATP

7. ATP
• ATP is the most important energy molecule needed for survival
• Used for daily function of the cell
• All the chemical reactions in the cell are called its metabolism

8. Cellular respiration
• Cellular respiration (aerobic) and fermentation
(anaerobic) oxidize (removes electrons from) glucose
and convert this chemical energy into ATP
ATP
Sugar
Glycolysis
Anaerobic
Respiration
(Fermentation)
Aerobic
Respiration
ATP
ATP
ATP
ATP

9. glycolysis
• 1st step in aerobic cellular respiration or
fermentation
• Occurs in ALL cell types (including plants and
bacteria)
• 10 reactions
• 2 ATP molecules
• Occurs in the cytoplasm
• Next step varies depending on the presence of
oxygen
Sugar
Glycolysis ATP

10. Aerobic Cellular respiration
• WITH Oxygen
• Most efficient way to produce ATP
• Can produce 38 ATP from each glucose molecule!
• Chemical equation:
• C6H12O6 + O2  CO2 + H2O + ATP
• 3 stages
• Glycolysis (2 ATP)
• Occurs in the cytoplasm
• Kreb’s cycle (2 ATP)
• Occurs in the mitochondria
• CO2 is a waste product
• Electron transport chain (34 ATP)
• Occurs in the mitochondria
• H2O is a waste product
Sugar
Glycolysis
Aerobic
Respiration
ATP
ATP
ATP
ATP

11. Fermentation (Anaerobic respiration)
• WITHOUT Oxygen: Anaerobic respiration
• Glycolysis
• Fermentation
• Occurs in the cytoplasm like glycolysis
• Produces 2 ATP per glucose molecule
• 2 Types of fermentation
• Alcoholic
• Yeast and bacteria
• Ethanol and CO2 are byproducts
• Lactic acid
• Muscle cells (during strenuous exercise – oxygen debt)
• Lactic acid is a byproduct
Sugar
Glycolysis
Anaerobic
Respiration
(Fermentation)
ATP
ATP

12. summary

13. Photosynthesis and Cellular respiration
• OPPOSING REACTIONS!
• Photosynthesis
• Carbon dioxide plus water yields (in the presence of
sunlight) glucose plus oxygen
• CO2 + H2O  C6H12O6 + O2
• Cellular respiration
• Glucose plus Oxygen plus ATP yields Carbon Dioxide
plus Water
• C6H12O6 + O2  CO2 + H2O
sunlight

15. reactants of
cellular
respiration
Glucose and Oxygen

16. products of Cellular
respiration
Carbon Dioxide and Water

17. Most atp is
produced during...
Electron transport chain

18. fermentation
anaerobic
Aerobic, anaerobic, or both?

19. Electron transport
chain
aerobic
Aerobic, anaerobic, or both?

20. Requires oxygen
aerobic
Aerobic, anaerobic, or both?

21. Does not require
oxygen
anaerobic
Aerobic, anaerobic, or both?

22. glycolysis
both
Aerobic, anaerobic, or both?

23. Krebs cycle
aerobic
Aerobic, anaerobic, or both?

24. Cellular respiration
releases energy
by...
Breaking down glucose

25. How is atp used for
energy?
Broken bonds between phosphate
groups release energy

26. This part of Atp
Phosphate

27. This part of Atp
Ribose sugar

28. This part of Atp
Adenine base

29. Metabolism is...
All the chemical reactions in a cell

30. What cellular
respiration process
occurs in the
cytoplasm?
Glycolysis and fermentation

31. What cellular
respiration process
occurs in the
mitochondria?
Kreb’s cycle and Electron Transport
Chain (ETC)

32. Why is the
mitochondria the
powerhouse of the
cell?
It produces the most ATP

33. Why can some cells
not have a
mitochondria?
They go through
glycolysis/fermentation