Photosynthesis

Question 1

What are this first step of photosynthesis

Answer 1

1) Photon absorption by PSII reaction center and generation of O2. 4 Electrons generated from 2 molecules

Question 2

What is the second step of photosynthesis

Answer 2

electrons flow through the etc, including electron carriers PQ, PC and Cyt b6f

Question 3

What is the third step of photosynthesis

Answer 3

Photon absorption by PSI reaction centre, final electron acceptor is NADP+

Question 4

What is the fourth step on photosynthesis

Answer 4

Photophsophorylation occurs

Question 5

What is the fifth step of photosynthesis

Answer 5

CO2 fixation in the calvin cycle to form G3P

Question 6

Where is ATP synthesis occuring

Answer 6

In the stroma

Question 7

What does the calvinc cycle produce

Answer 7

G3P and CO2

Question 8

What does photosynthesis accomplish for the cell

Answer 8

Converts light energy to redox energy, used to generate ATP and reduce NADP to NADPH. Calvin cycle uses ATP and NADPH to reduce CO2 to form G3P

Question 9

What is hte net reaction of the Photosynthetic ETC

Answer 9

2H2O + 8 photons + 2 NADP + 3ADP + 3Pi –> O2 + 2 NADPH + 3 ATP

Question 10

What is the net reaction of the Clavin Cycle

Answer 10

3 Co2 + 6 NADPH + 9ATP + 5H2O –> G3P + 6 NADP + 9ADP + 8 Pi

Question 11

What are the key enzymes in photosyntehsis

Answer 11

PSII, cytochrome b6f, PSI

Question 12

Photosynthetic pigments absorb light in the _____ range of the spectrum

Answer 12

visible

Question 13

carotenoids absorb in the ____ range which is why they appear _____

Answer 13

blue, orange

Question 14

what are the major pigments in green plants

Answer 14

chlorophyll a, b and carotenoids

Question 15

what is the role of LHC II

Answer 15

functions as a solar panel that harvests light energy for PSII and PSI

Question 16

What is noncyclic electron transfer

Answer 16

Electron transfer from H2O to NADP to produce NADPH
2 electrons must be lifted twice
4 protons translocated

Question 17

what is cyclic electron transfer

Answer 17

alternative path of electrons, electrons move from ferredoxin back to cyt b6f complex

Question 18

What is the role of cyanobacteria

Answer 18

use cytochrome b6f, cytochrome c6 and plastoquinone for both oxidative and photoposphorylation

Question 19

How many electrons are needed to reduce 2PQB to 2PQBH2

Answer 19

4

Question 20

What happens in the PQ cycle

Answer 20

8 H are translocated in PSII and cytochrome b6f. 4H generated by oxidation of 2H2O to O2, leading to net gain of 12 H

Question 21

What happens when NADP levels are high in the stroma

Answer 21

leads to electron flow between ferredoxin and plstiquinone in PSI

Question 22

In mitochondria and bacteria protons are pumped ___ of the organelle, while chloroplasts protons are pumped ___ of the organelle

Answer 22

out, in

Question 23

What is stage 1 of the calvin cycle

Answer 23

RuBP combines with CO2 , then cleaves two C3 molecules of 3-phosphoglycerate

Question 24

What is stage 2 of the calvin cycle

Answer 24

3-phosphoglycerate is reduced to g3p using ATP and NADPH

Question 25

What is stage 3 of the calvin cycle

Answer 25

5 G3P are used to resynthesize 3 ribulose 1,5 biphosphate in a carbon shuffle that requires ATP

Question 26

G3P are building blocks for what?

Answer 26

for hexose sugars

Question 27

What is the glyoxylate cycle in plants

Answer 27

provides a mechansms for fats stored in seeds to be converted to surcose for export

Question 28

In chloroplast, ATP synthase releases newly synthesized ATP into the _____

Answer 28

stroma

Question 29

What are the differences between Chlorophyll and Heme

Answer 29

Chlorophyll coordinates with Mg ion and has a hydrophobic tail, while Heme coordinates with Fe ion and lacks hydrophobic tail

Question 30

for every four reduced PQBH2 molecules that are oxidized in PQ cycle, how many protons are translocated to the thylakoid lumen?

Answer 30

8

Question 31

where are electron carriers from PSI stored

Answer 31

in the thylakoid lumen

Question 32

Where does the CO2 come from that is used in the Calvin cycle

Answer 32

from the air

Question 33

Calvin cycle inhibitors are more present in the dark or light?

Answer 33

dark

Question 34

Calvin cycle enzymes are activated by a ______ in proton concentration and _______ in Mg levels in the stroma

Answer 34

decrease, increase