What is the pathway of c3 and c4 cycle - Biology - Respiration in Plants

Question

What is the pathway of c3 and c4 cycle???

Fakeha Anis · Accepted Answer

Dear student,;
Please find below the answer:

C3 cycle or we can say Calvin cycle Occurs in higher plants to
capture the carbon dioxide and produce 2 molecules of
glyceraldehyde-3 phosphate from which one molecule is used in other
reactions and other gets converted back into RuBP to repeat the
reaction again
C3 cycle has three phases:-
1 Carbon fixation:- in this phase RuBP (
Ribulose-1,5-bisphosphate)
reacts with the carbon dioxide to form a six carbon intermediate
that gets converted into 2 molecules of 3-phosphoglycerate This
reaction use an enzyme known as Rubisco

2

Reduction:-
in this phase formed 2 molecules of 3-phosphoglycerate gets
converted into 2 molecules of glyceraldehyde-3 phosphate using ATP
and NADPH2

3

Regeneration:-
in this phase 1 molecule of glyceraldehyde-3 phosphate is used in
other reactions whereas other molecule gets converted into RuBP
using ATP, thus completing the C3 cycle

C4 cycle occurs in two types
of cells mesophyl cells and bundle sheath cells

In mesophyll cells the pyruvate is converted
into the phosphoenolpyruvate using ATP

Then this phosphoenolpyruvate reacts with the
carbon dioxide to form oxalooacetate

then this oxaloacetate is finally converted
into the malate that is transported to the bundle sheath cells to
release carbon dioxide there that can be used in the calvin
cycle

Hope this clears your doubt
Regards