Question

what is the function of NADPH in Photosynthesis, i know it can help to product organic molecules, but how it works?

Answer 1

NADPH is a reducing agent, also known as an electron transporter, it essentially gets oxidized to NADP+, which results in the release of energy.

It is formed in the last step of the calvin cycle, it is also formed in the pentophosphate pathway (an alternative pathways to the TCA cycle)

It works just like NADH and FADH2 it as a way of transfering energy

According to Hess's law reactions can be coupled together, enzymes can help to coupling the oxidiation of NADP+ to other otherwise unfavourable reactions to make them proceed forword

Answer 2

Does that help or do you want to know exactly how NADP+ is higher energy than NADPH

Answer 3

http://dehydrogenase.co.uk/NADP/nadp-01.png
The image depicts the formation of NADPH from NADP+

as you can see NADPH has a high energy phosphate bond that it essentially loses when it is oxidized to NADP+ resulting ina free phosphate forming and energy being released.

Answer 4

You can also kind of think of it as ATP and GTP although ATP and GTP carry significantly more chemical potential energy than the electron transporters.

Answer 5

oops made a mistake,

"According to Hess's law reactions can be coupled together, enzymes can help to coupling the oxidiation of NADPH to other otherwise unfavourable reactions to make them proceed forword"

Answer 6

oops I messed up NADPH is oxidized in the last step of the cori cycle

Answer 7

http://www.uic.edu/classes/bios/bios100/f05pm/calvin.jpg

Cori Cycle

Answer 8

Is my explanation helping at all?

Answer 9

blah Im all over the place that is the calvin not the cori lol

Answer 10

But essentially,

NADPH -> P + NADP+ + Energy

Answer 11

The body stores energy in chemical bonds in molecules

Answer 12

If you wondering how the body can couple these reactions it has to do with how enzymes can help to coordinate molecules together pushing equilibrium forward.

Not that I'm saying that enzyme increase the amount of product you acquire at equilibrium! No enzyme can do this, they simply increase the speed at which you reach equilibrium (increasing the rate of the reaction)

Answer 13

well actually stabalizing the transition state is a big factor as well in enzymes ability to catalyze reactions

Answer 14

does the NADPH release the P to help some enzyme to process the calvin cycle and acts as a kinds of allosteric regulation that amplify enzyme activity

Answer 15

am i right?

Answer 16

Blahhhh everything I wrote I lost lol

Answer 17

Essentially what is happening is the last step is NADPH is transfering a phosphate group 3-phosphoglycerate, this is often done as a way of transfering energy to the substrate so that the breaking of the phosphate group off can fuel another chemical transformation of it

Answer 18

Im not sure you are correct about the regulation tbh Im not too familure with the calvin cycle. If you are very interested in its regulation you should look up a review paper on it, wikipedia seems to have a decent outline of it as well

Answer 19

tks, i will do it. XD

Answer 20

NADPH is mainly formed in the pentose phosphate pathway though from my knowledge

Answer 21

there are probably regulating factors that keep the pathway from running in reverse though

Answer 22

tk u very much. English is not my first language so it's a little difficult for me to learn biology(my biology textbook is wrote in English) @^@

Answer 23

Well yeah english is the official language of science, I'm sure you can find some reasources in your native language as well if you look hard enough.

I think the best way to work with these pathways is to learn about every enzyme involvd in the pathway individual and what affects it. Essentially write a story.

Answer 24

individually*

Answer 25

you should check out "molecular biology of the cell", it is a pretty good text book for this stuff

Answer 26

actually im reviewing this part XD

Answer 27

tk u again ………………^^

Answer 28

http://i.imgur.com/q1mh4AA.png