Chapter 10

Question 1

the Calvin cycle occurs in the:

Answer 1

stroma

Question 2

the Calvin cycle forms:

Answer 2

sugar from CO2 using ATP and NADPH

Question 3

carbon fixation

Answer 3

the Calvin cycle begins with this step in which it incorporates CO2 into organic molecules

Question 4

linear electron flow:

Answer 4

the primary pathway, involves both photosystems and produces ATP and NADPH using light energy

Question 5

8 steps of linear electron flow:

Answer 5

1. A photon hits a pigment and its energy is passed among pigment molecules until it excites P680
2. An excited electron from P680 is transferred to the primary electron acceptor (now called P680+)
3. Water is split by enzymes, and the electrons are transferred from the hydrogen atoms to P680+, thus reducing it to P680 (O2 is released as a by-product of this reaction)
4. Each electron “falls” down an electron transport chain from the primary electron acceptor of PS II to PS I
5. Energy released by the fall drives the creation of a proton gradient across the thylakoid membrane (diffusion of the H+ (protons) across the membrane drives ATP synthesis)
6. in PS I (like PS II), transferred light energy excites P700, which loses an electron to an electron acceptor (P700+ accepts an electron passed down from PS II via the electron transport chain)
7. each electron “falls” down an electron transport chain from the primary electron acceptor of PS I to the protein ferredoxin (Fd)
8. the electrons are then transferred to NADP+ and reduce it to NADPH (also removes H+ from the stroma)