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a level biology - light dependent and light dependent reaction

zarahh09

Can someone please explain to me the steps involved in the light dependent and light independent reaction

Reply 1

CaptainDuckie

Study Forum Helper

What does the textbook say?

Here are keywords from the top of my head, try and formulate an answer

keywords
Photolysis
electrons
Photo system I and II
electron carrier
ATP synthase
ADP
NADP reductase
GP
TP
carbon fixtation
Regeneration
Reduction
Rubisco
Rubp
Co2
Starch, glucose

Reply 2

CaptainDuckie

Study Forum Helper

I’ll try to mark it, if you want. Why not?

Reply 3

zarahh09

Original post by CaptainDuckie

We haven't got the text books yet as this is our 2nd year stuff. We are told to do this as preparatory work

Reply 4

CaptainDuckie

Study Forum Helper

Original post by zarahh09

We haven't got the text books yet as this is our 2nd year stuff. We are told to do this as preparatory work

What exam board? Have you tried looking on YouTube?

Reply 5

zarahh09

Original post by CaptainDuckie

What exam board? Have you tried looking on YouTube?

Salters nuffield A

Reply 6

Hellllpppp

Original post by zarahh09

We haven't got the text books yet as this is our 2nd year stuff. We are told to do this as preparatory work

If you haven’t got a textbook yet u could try using the physics and maths tutor summary notes

Reply 7

CaptainDuckie

Study Forum Helper

Original post by zarahh09

Salters nuffield A

Have a read at Khan Academy

If you read all of it, you should have complete understanding of the processes.

Reply 8

zarahh09

Original post by CaptainDuckie

I’ll try to mark it, if you want. Why not?

Step 1 - light dependent :
Carbon dioxide and water enter the leaf

Step 2 - light dependent :
Light his the pigment in the membrane of thylakoid, splitting water into oxygen

Step 3 - light dependent :
The electrons move down to enzymes

Step 4 - light dependent :
Sunlight hits second pigment molecule allowing enzymes to convert ADP to ATP and NADP+ gets converted to NADPH

Step 5 - light independent :
The ATP and NADPH is used by calvin cycle as a power source for converting carbon dioxide from atmosphere into simple sugar glucose

Step 6 - light independent :
calvin cycle converts 3CO2 molecules from the atmosphere to glucose

I trid this but idk if this is right though

Reply 9

CaptainDuckie

Study Forum Helper

Original post by zarahh09

Missing quite a lot of detail out, but then again not sure how much you’re required to know for your exam board etc.

Try looking through your specification here

In addition to that Khan Academy link I sent above and try formulating an answer. I’ll look through your spec point and see.

Reply 10

CaptainDuckie

Study Forum Helper

It says

5.7 Understand the light-dependent reactions of photosynthesis including how light energy is trapped by exciting electrons in chlorophyll and the role of these electrons in generating ATP, reducing NADP in photophosphorylation and producing oxygen through photolysis of water.

5.8 i) Understand the light-independent reactions as reduction of carbon dioxide using the products of the light-dependent reactions (carbon fixation in the Calvin cycle, the role of GP, GALP, RuBP and RUBISCO).
ii) Know that the products are simple sugars that are used by plants, animals and other organisms in respiration and the synthesis of new biological molecules (polysaccharides, amino acids, lipids and nucleic acids).