Section 17 fill-in-the-blank – 0.5 pts ea
During stage III of cell respiration, reduced
coenzymes are produced during the
metabolic pathway known as Kreb’s cycle,
which takes place in the matrix of the
mitochondrion. During stage IV, a proton
gradient is established across a membrane
due to flow of electrons from 1 complex to
next, with final oxidizing agent being O2.
This gradient is dissipated during chemiosmosis, which is the diffusion of protons
through ATP synthase, making ATP.
In chloroplasts, the process is similar, except that
the original source of electrons is H2O, and the
final oxidizing agent in non-cyclic photophosphorylation is NADP. The light-independent
reaction, or Calvin cycle takes place in the stroma
of chloroplasts. In C3 plants, such chloroplasts
would be conducting this cycle in mesophyll cells;
in C4 plants it would be done in bundle sheath
cells. CAM plants, such as cactuses and
bromeliads carry out the light and light-independent reaction at (during) daytime and fix CO2 at
night. In these plants, the 1st stable product of
fixation is 4-C compounds. The enzyme which
carboxylates RuBP in these plants is RUBISCO.