Clear this up for me please...Easy question about photosynthesis

[Cofo]

---

Members don't see this ad.

The two energized electrons from PSII that lose most of their energy when being passed down the electron transport chain...do these very same two electrons become captured by PSI, where they become re-energized by sunlight?
I just wanted to know if someone could clear this up for me.

 

[Alekshura2]

The absorbed energy excites electrons to a highte energy level. So the energized electrons from photosystem I are passed on through the electron transport chain and added to NADP+ to make NADPH. Meanwhile, energized electrons from Photosystem II, (what you are asking about,) are passed through another electron transport chain and their energy is used to pump hydrogen ions from stroma into the thylakoid compartment and this creates a concentration gradient. The same electrons leave the electron transport chain and enter photosystem I repleneshing its lost electrons that were used to make NADPH. Photosystem II repleneshis its electrons by splitting water.
Hopefully this answers your questions.

 

[Cofo]

The absorbed energy excites electrons to a highte energy level. So the energized electrons from photosystem I are passed on through the electron transport chain and added to NADP+ to make NADPH. Meanwhile, energized electrons from Photosystem II, (what you are asking about,) are passed through another electron transport chain and their energy is used to pump hydrogen ions from stroma into the thylakoid compartment and this creates a concentration gradient. The same electrons leave the electron transport chain and enter photosystem I repleneshing its lost electrons that were used to make NADPH. Photosystem II repleneshis its electrons by splitting water.
Hopefully this answers your questions.

...Wrong, wrong, wrong, wrong....YOU'RE WRONG!!

 

[Alekshura2]

Ok then please clear it up for me. I thought this was correct from what i remember from biochem.

 

[wantVCUdental]

The two energized electrons from PSII that lose most of their energy when being passed down the electron transport chain...do these very same two electrons become captured by PSI, where they become re-energized by sunlight?
I just wanted to know if someone could clear this up for me.

Hi Cofo, i recommend not getting down to the nitty grittys when you are studying for the DAT 😀, knowing which precise electrons travel through the ETC will not increase your score by much 😉

To answer your question, it COULD be the exact same two electrons, but it could be some other electrons that get re-energized. This can be understood with the help of organic chemistry. What are PSI and PSII? they are big organic molecules with resonance structures. The places where electrons can be "accepted" or "given up" are only at resonance stable parts. Now once the electrons are accepted by PSII, where they join the electron cloud of PSII, they COULD be the ones that are excited by light or another two electrons in the resonance could be excited.
Hope this helps

 

[peanutb123]

...Wrong, wrong, wrong, wrong....YOU'RE WRONG!!

look at animations...