Photosynthesis
Where do the light reactions of photosynthesis occur?
thylakoid
1) Photons excite pigment molecules. 2) Rubisco catalyzes the fixation of CO2 to RuBP. 3)An enzyme catalyses the reduction of 1,3BPGA by NADPH. 4)An enzyme catalyzes the phosphorylation of 3-PGA. 5)An unstable molecule splits into two molecules of 3-PGA. 6)A CO2 molecule enters the cycle. 7)G3P molecules are rearranged to produce RuBP.
1) NOT A STEP 2)step 2 3) step 5 4)step 4 5) step 3 6)step 1 7) step 6
The Calvin cycle could not occur without the light reactions. Which of the following statements describes why this is the case?
ATP and NADPH produced in the light reactions provide the energy for the production of sugars in the Calvin cycle
What happens during the first phase of the calvin cycle?
CO2 is attached to RuBP
Which occurs during the Calvin cycle?
CO2 is reduced
What occurs in the stroma?
Calvin Cycle carbon fixation
What property of the pigment chlorophyll makes it appear green?
Chlorophyll absorbs all of the visible spectrum of light except green, which it reflects.
A photosystem consists of which of the following structures?
Light-harvesting complexes Reaction-center complex Primary electron acceptor Chlorophyll molecules
Imagine that light reactions produced only half the ATP that they actually do. What would be required to maintain the Calvin cycle at the same rate?
More h20
Where does the energy used to produce ATP in the light reactions of photosynthesis come from?
Movement of H+ through a membrane
The light reactions of photosynthesis generate high-energy electrons, which end up in __________. The light reactions also produce __________ and __________.
NADPH; ATP; oxygen
In the light reactions of photosynthesis, ATP is produced by photophosphorylation. Which of the listed processes is most similar to photophosphorylation?
Oxidative Phosphorylation
Regarding the Calvin cycle, which are correct?
Produces NADP+, ADP and Uses ATP and NADPH Occurs in the stroma Uses CO2 and produces GP3.
Why do the reactions of the Calvin cycle usually not occur at night?
The Calvin cycle requires products of the photosystems
During which process is molecular oxygen produced in photosynthesis?
The light reactions by linear electron flow
What happens when chloroplast pigments absorb light?
Their electrons become excited
Why are most autotrophs referred to as the producers of the biosphere?
They are the ultimate sources of organic compounds for all nonautotrophic organisms.
Chlorophyll molecules are in which part of the chloroplast?
Thylakoid membranes
Regarding the Calvin cycle, which are correct?
Uses ATP and NADPH Uses CO2 and produces GP3. Occurs in the stroma Produces NADP+, ADP and
Regarding the light reactions phase of photosynthesis, which are correct?
Uses H2O and releases O2 Uses NADP+, ADP and Occurs in the thylakoid Uses light energy to excite electrons Produces ATP and NADPH
In photosynthesis, what molecule is oxidized and what molecule is reduced?
Water is oxidized and carbon dioxide is reduced.
You have a large, healthy philodendron that you carelessly leave in total darkness while you are away on vacation. You are surprised to find that it is still alive when you return. What has the plant been using for an energy source while in the dark?
While it did have access to light, the plant stored energy in the form of sugars or starch, and it was able to derive energy from the stored molecules during your vacation.
What do the light reactions of photosynthesis supply the Calvin cycle with?
atp and nadph
What is the most important role of pigments in photosynthesis?
capture light energy
What is the source of the carbon plants use to make organic molecules?
carbon dioxide
Phases of calvin cyle
carbon dioxiode reduction regeneration
Which processes are used in both cellular respiration and photosynthesis?
electron transport chains chemiosmosis
Which processes are used in both cellular respiration and photosynthesis?
etc chemiosmosis
Which of the following processes occurs during the second phase of the Calvin cycle?
g3p production
How does carbon dioxide enter a leaf?
stomata
Put these leaf structures in order, from outermost to innermost.
stomata 1 mesophlly 2 chloroplast 3 stroma 4 thylakiods 5 chlorophlly 6
The light reactions of photosynthesis use chemiosmosis to produce ATP that will be used in the Calvin cycle. The electrochemical gradient that drives this chemiosmosis is formed across which structure(s)?
thylakoid membrane
Both mitochondria and chloroplasts __________.
use chemiosis to produce atp
What is the source of the oxygen produced by photosynthesis?
water
Where do the electrons entering photosystem II come from?
water
Correct Answers Your Choices Cell where photosynthesis takes place Mesophyll Fluid inside a chloroplast Stroma Single unit of membranous sac Granum Internal membrane of a chloroplast Thylakoid Organelle in which photosynthesis takes place Chloroplast Allow diffusion of CO2 Stomata
yes