Photosynthesis, Cellular Respiration- Conservation of Energy

[PPonte]

Photosynthesis is the process by which plants, some bacteria, and some protistans use the energy from sunlight to produce sugar, which cellular respiration converts into ATP, the "fuel" used by all living things.

The photosynthesis overall reaction can be written as:

6H2O + 6CO2 → C6H12O6+ 6O2
Consumes 18 ATP molecules per glucose(Calvin Cycle).


C6H12O6 + 6O2 → 6CO2 + 6H2O
Yields 36/38 ATP molecules per glucose.

As they are inverse reactions, although carried by different processes, the energy consumed in Photosynthesis to produce one glicose (18 ATP), shouldn't be equal to the number of ATP molecules yield by oxidation of one glicose in Cellular Respiration? Or, in the last mentioned process, there is an input of energy that I didn't notice?

Thank you.

[victor]

I can think that 18 ATP which is consumed in Calvin cycle is not to produce glucose, but PGAL / G3P(phospoglyceraldehyde / glyceraldehyde-3-P).

And, 2 molecules of G3P equals one molecule of glucose...so??:lol:

[rimasima]

[b] Hi I am really stuck on what do to 4 my assignment piece like we have to do some experiment dealing with C3 C4 plants and I was wondering if someone could help me out please I really need some help...can anyone help? Its a 10000word essay


From sarima [/b]

[victor]

Umm...you can start it by searching species which undergoes each C3 nad C4 mechanism. If you understand the processes, I bet you can create your own experiment..