Download Calvin Cycle Answers

Calvin Cycle Answers
1. Stroma
2. Because inorganic CO2 is put into a biological molecule
eventually used to make organic glucose.
3. Because it needs to happen 3 times to fix enough carbon for
1 PGA/G3P.
4. Because it catalyzes 2 reactions – reduction of RuBP and
regeneration of RuBP so CO2 and O2 are competing for the
same active site.
5. The light reactions: cyclic and non-cyclic electron
pathways.
6. NADPH is oxidized. PGAP/1,3-Bisphosphoglyerate is
reduced.
7. Out of 6 PGAL/G3P molecules in each cycle only 1 is used
to make glucose – the others are used to regenerate RuBP.
8. As shown in the book or handout, 2 times.
9. Do it yourself.
10.
a) 3 ATP, 2 NADPH
b) 2 ATP, 2 NADPH
c) The cyclic electron pathway produces ATP
11.
a) Because the first product is a 3 carbon molecule
b)
C3
C4
Corn
Examples Wheat
Calvin cycle occurs in
Differences As shown in
book/handout Bundle Sheath cells,
in Calvin
where CO2 concentration
Cycle
is higher than in
atmosphere.
Temperate (ex. Tropical (ex. Cuba)
Climate
here)
c) The rate of reaction of the Calvin cycle increases with
temperature up to 37◦C, but above 25◦C, Rubisco (RuBP
carboxylase) oxidizes RuBP more, so little carbon
fixation occurs.
12.
3 CO2 + 9 ATP + 6 NADPH + 6 H2O
9 ADP +
+
9 Pi + 6 NADP + PGAL/G3P
(for each PGAL/G3P produced.)