Title: Ch' 6: How Cells Harvest Chemical Energy
1Ch. 6 How Cells Harvest Chemical Energy
2Energy Flow
- Photosynthesis
- O2 glucose
- Cellular Respiration
CO2 H2O
ATP
Heat
3 Recycling
- The chemical elements essential to life are
recycled. - Energy is NOT recycled
- Harvesting of chemical energy
- complex
- organic
- molecules
Simpler waste products with less energy.
Catabolic pathway
ENERGY some used to do work, some dissipated as
heat
4Two types of cellular respiration
- 1. Aerobic respiration
- final electron acceptor is O2
- 2. Anaerobic respiration
- final electron acceptor is not O2
- fermentation
5Aerobic Cellular Respiration
- Organic molecules O2
- CO2 H2O Energy
6Redox Reactions
- Always occur together
- Involves the removal of electrons from one
molecule (oxidation), and the transfer of these
electrons to some other molecule (reduction) - In cells, the electron often belongs to a
Hydrogen atom.
7Generation of ATP
- Decarboxylation
- decarboxylases
- Dehydrogenation
- dehydrogenases
- Function of NAD, FAD
8Aerobic Cellular Respiration
- 1. Glycolysis
- 2. Kreb Cycle
- 3. Electron Transport Chain
So, what do I have to know about each of
these metabolic pathways?
9- So, what do I have toknow about each of
thesemetabolic pathways?
1. Initial reactants and final products 2.
Location of each pathway 3. How much ATP is
produced 4. Purpose of each metabolic pathway 5.
Decarboxylation, Dehydrogenation 6. Aerobic or
Anaerobic 7. Final electron acceptor
10Anaerobic Respiration
- E.g. fermentation
- Alcoholic fermentation
- Acidic fermentation
- glycolysis fermentation
11Why ask why?
- So, why would an organism undergo fermentation
when it can make so much more ATP from aerobic
respiration?