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Can I call reduced NADP 'NADPH'?

And reduced NAD, NADH? I know this is what they ARE called, but the AQA sylabbus always refers to it as "reduced NADP". Will they accept NADPH in its place?

Also, I understand that the NAD and NADP are nor gaining hydrogen atoms when they are being reduced, this is evident in their molecular structures. So why is it normal to call the reduced versions NADH and NADPH?

Reply 1

igloo1

NADPH is fine.
They are gaining hydrogen ions (protons) so become reduced. This won't change the structure.

Reply 2

nicatre

They gain electrons to become reduced as hydride ions (H-).

Reply 3

Anniestasia

This is what we write as shorthand in our college, and its right, but not sure if the exam board will accept it!

Reply 4

byebyebadman

Original post by igloo1

NADPH is fine.
They are gaining hydrogen ions (protons) so become reduced. This won't change the structure.

Gaining protons would mean they are being oxidised. They are certainly gaining electrons. And the structure does change. See:

I still don't understand the exact chemistry behind it. But it seems as though NAD is gaining a whole H atom, whilst gaining a net reduction in oxidation state.

Reply 5

DrAtticusFinch

AQA accept NADPH as an alternative to reduced NADP.

Reply 6

igloo1

Original post by byebyebadman

Gaining protons would mean they are being oxidised. They are certainly gaining electrons. And the structure does change. See:

I still don't understand the exact chemistry behind it. But it seems as though NAD is gaining a whole H atom, whilst gaining a net reduction in oxidation state.

I don't know about the chemistry behind it, I dont think you need to know the structure or anything for AQA. Just know water is split and photolysis happens leaving a H+ which reduces NADP to NADPH, whilst the electrons replace lost electrons in the chlorophyl, and they in turn are used to make ATP.

Reply 7

byebyebadman

Original post by igloo1

How are they (the electrons lost in the chlorophyll) used to make ATP? I understand they are excited to an excited state and picked up by electron carriers, and eventually passed to NADP as the final electron carrier. But I thought ATP was made via chemiosmososis and the proton gradient built up as result of the photoloysis?

Reply 8

igloo1

Original post by byebyebadman

Have a look at this guy. He always helps me with biology.
http://www.youtube.com/watch?v=2IygaV0_-B0
I don't think you need to know more than that. Don't even think you need to know about the 2 photosystems ( you'll see what i'm on about).
Just know - ATP can be made by when electrons de-excite down electron carriers because they lose energy. This " lost" energy is used in combining ADP and phosphate to make ATP.
And, my teacher taught me that too. To be honest, i've been taught both. I'm thinking the one i'm describing is the simpler one and it depends on the question. I have no idea. Ask your teacher would be my best advice.
Sorry if i've confused you.. :colondollar: