Which of the following is mismatched with its
- light reactions--grana
- electron transport chain--thylakoid
- Calvin cycle--stroma
- ATP synthase--double membrane
- Splitting of water--thylakoid space
Photosynthesis is a redox process in which.
- CO2 is reduced and water is
- NADP+ is reduced and RuBP
- CO2, NADP+, and
water are reduced.
- O2 acts an oxidizing agent
and water acts as a reducing agent.
- G3P is reduced and the electron
transport chain is oxidized.
Blue light has more energy than red light.
- Has a longer wavelength than red light.
- Has a shorter wavelength than red
- Contains more photons than red light.
- Has a broader electromagnetic spectrum
than red light.
- Is absorbed faster by chlorophyll a.
A spectrophotometer can be used to measure
- The absorption spectrum of a substance.
- The action spectrum of a substance
- The amount of energy in a photon.
- The wavelength of visible light.
- The efficiency of photosynthesis.
Accessory pigments within chloroplasts are
- Driving the splitting of water
- Absorbing photons of different
wavelengths of light and passing that energy to P680 or P700.
- Providing electrons to the
reaction-center chlorophyll after photo-excited electrons pass to NADP+.
- Pumping H+ across the
thylakoid membrane to create a proton-motive force.
- Anchoring chlorophyll a within the
Noncyclic electron flow in the chloroplast results
- ATP only.
- ATP and NADPH.
- ATP and G3P.
- ATP and O2.
- ATP, NADPH, and O2.
The chlorophyll known as P680 has its electron
"holes" filled by electrons from
- photosystem I.
- Photosystem II.
- Accessory pigments.
CAM plants avoid photorespiration by
- Fixing CO2 into organic
acids during the night; these acids then release CO2 during
- Performing the Calvin cycle at night.
- Fixing CO2 into four-carbon
compounds in the mesophyll, which release CO2 in the
- Using PEP carboxylate to fix CO2
to ribulose bisphosphate (RuBP).
- Keeping their stomata closed during
Electrons that flow through the two photosystems
highest potential energy in
- The electron transport chain.
- Photo-excited P700.
Chloroplasts can make carbohydrate in the dark if
- ATP and NADPH and CO2.
- An artificially induced proton
- Organic acids or four-carbon compounds.
- A source of hydrogen.
- Photons and CO2.
In the chemiosmotic synthesis of ATP, H+
through the ATP synthase
- From the stroma in the thylkoid space.
- From the thylakoid space into the
- From the cytoplasm into the matrix.
- From the cytoplasm into the stroma.
- From the matrix into the stroma.
In C4 plants, the Calvin cycle
- Takes place at night.
- Only occurs when the stomata are
- Takes place in the mesophyll cells.
- Takes place in the bundle-sheath cells.
- Uses PEP carboxylase instead of
rubisco because of its greater affinity for CO2.
How many "turns" of the Calvin cycle are required
produce one molecule of glucose?
In green plants, most of the ATP for synthesis of
cytoplasmic streaming, and other cellular activities comes directly from
- Photosystem I.
- The Calvin cycle.
- Oxidative phosphorylation.
- Noncyclic photophosphorylation.
- Cyclic photophosphorylation.
The six molecules of G3P formed from three turns
of the Calvin
cycle are converted into
- Three molecules of glucose.
- Three molecules of RuBP and one G3P.
- One molecule of glucose and four
molecules of 3-phosphoglycreate.
- One G3P and three four-carbon
- None of the above, since three
molecules of G3P result from three turns of the Calvin cycle.
A difference between chemiosmosis in
respiration is that in photophosphorylation
- NADPH rather than NADH passes
electrons to the electron transport chain.
- ATP synthase releases ATP into the
stroma rather than into the cytosol.
- Light provides the energy to push
electrons to the top of the electron chain, rather than energy from the
oxidation of food molecules.
- An H+ concentration
gradient rather than a proton-motive force drives the phosphorylation
- Both a and c are correct.
NADPH and ATP from the light reactions are both
- In the carbon fixation stage to
provide energy and reducing power to rubisco.
- To regenerate three RuBP from five G3P (glyceraldehyde 3-phosphate).
- To combine two molecules of G3P to
- To convert 3-phosphoglycerate to G3P.
- To reduce the H+
concentration in the stroma and contribute to the proton-motive force.
What portion of an illuminated plant cell would
you expect to
have the lowest pH?
- stroma of chloroplast
- thylakoid space
How does cyclic electron flow differ from
- No NADPH is produced by cyclic
- No O2 is produced by cyclic
- The cytochrome complex in the electron
transport chain is not involved in cyclic electron flow.
- Both a and b are correct.
- A, b, and c are correct.
What does rubisco do?
- reduces CO2 to G3P
- regenerates RuBP with the aid of ATP
- combines electrons and H+
to reduce the NADP+ to NADPH
- adds CO2 to RuBP in the
carbon fixation stage
- transfers electrons from NADPH to
1,3-bisphosphoglyceerate to produce G3P