Photosynthesis vs Cellular Respiration

Photosynthesis: Synthesizing molecules from smaller components in order to store energy, requires energy in the process.
- Noncyclic Photophosphorylation

• P680 absorbs a photon, the excited electron goes to b6-f complex, then to P700 where electrons get excited by NADP reductase to reduce NAP+.
• Oxygen and NADPH are formed
• can produce ATP

- Cyclic Photophosphorylation:

• electron in P700 is excited by a photon, instead of being used to reduce NADP+ like in noncyclic photophosphorylation, electrons from Fd is passed to b6-f complex and back to P700.
• no NADPH or oxygen if formed
• can produce more ATP the little NADP is available.

- Calvin Cycle (light-independent):

• rubisco fixs CO2 and RuBP(5C) to become 2 PGA(3C) ---> 2 BPG(3C) ---> 2 G3P(3C)
• some G3P are used to make glucose, others recycled(G3Px2---> 1 glucose)
• uses ATP and NADPH

Cellular Respiration: breaking down complex molecules into smaller units, releasing energy.
 - Glycolysis:

• Glucose---> Glucose 6-phosphate ---> Fructose 6-phosphate ---> Fructose 1,6-phosphate ---> G3P---> 2 BPG ---> 3PG---> 2PG ---> 2 PEP --->2 pyruvate
• 2 ATP consumes, 4 ATP produced, 2 H2O produced

- Kreb's Cycle

• OXAL(4C) +Acetyl-CoA(2C) --->CIT(6C) ---> ISO(6C) --->alphaKG(5C) ---> Succinyl-CoA(4C) --->SUC(4C) ---> FUM(4C) ---> MAL(4C) ---> OXAL(4C)
• produces 2 ATP, 6 NADH, 2 FADH2

- Electron Tranport Chain:

• 2H+ ---> 1 ATP
• NADH passes 2 electrons to NADH dehydrogenase ---> bc1 complex ---> Cytochrome oxidase complex => 6 H+ 1 NADP ---> 3 ATP, 24 ATP(2 NADP from glycolysis behaves like FADH2)
• FADH2 passes 2 electrons to bc1 complex ---> Cytochrome oxidase complex => 4H+ 1 FADH2 ---> 2 ATP, 8 ATP