Chapter 8
What is the net gain of the Calvin cycle?
Two molecules of G3P
Which of the following are the two components of a photosystem?
a reaction center; an antenna complex
A photosystem consists of two components, a(n) ______ complex and a(n) _______ center.
antenna; reaction
Where does the Calvin cycle occur in a C4 plant?
bundle sheath cells
What molecule is released during photorespiration?
carbon dioxide
The Calvin cycle begins with ______.
carbon fixation using Rubisco
The two most important classes of pigments in chloroplasts are chlorophylls and ________
carotenoids
A leaf that appears green has more _______ than a leaf that appears yellow. A leaf may appear to be yellow due to ______ pigments.
chlorophyll; carotenoid/accessory
In the light-harvesting complex of the chloroplast, it is excitation _______, not the electrons themselves, that pass from one pigment molecule to the next.
energy
he ATP synthases of chloroplasts and mitochondria are ______.
evolutionary related
True or false: Glucose is the primary output of the Calvin cycle
false
True or false: The mechanism of ATP synthesis in the ATP synthase of chloroplasts is fundamentally different from the one used in the ATP synthase of mitochondria.
false
In the process of carbon ________, carbon dioxide is incorporated into a molecule of ribulose biphosphate forming an unstable 6 carbon intermediate that immediately splits into two 3-carbon molecules.
fixation
The light-______ reactions of photosynthesis occur on membranes.
light-dependent
The enzyme rubisco has more than one activity. Because of this, most plants also perform ______, which consumes oxygen and liberates carbon dioxide. This process can lower the net benefit from photosynthesis.
photorespiration
Photorespiration is considered "wasteful" because ______.
reduces the ability of a plant to make carbohydrates; it reduces the yield of photosynthesis
A leaf that appears to be green to the human eye contains pigment molecules that are ______.
reflecting green light
When light strikes a pigment, some wavelengths are absorbed and some are reflected. For instance, a leaf that appears green to the eye _________ green wavelengths of light.
reflects
The abbreviation, RuBP, stands for ________ 1,5-bisphosphate.
ribulose
Once a photon is captured by the light harvesting complex, the pigments in it transfer ______.
the energy of excited electrons but not electrons themselves
Typically, it is considered that the net gain of the Calvin cycle is(are) _______molecule(s) of G3P.
two
The oxidation potential of PSII is high enough that it can oxidize __________
water
In photosynthesis, CO2 is reduced to glucose using electrons from the oxidation of ______; in respiration, ________ is oxidized to CO2 using O2 as the final electron acceptor.
water; glucose
How many types of photosystems are found in chloroplasts?
2
The electron transport chain directly associated with photosystem II is used to generate ______, while the electron transport chain directly associated with photosystem I is used to generate ______.
ATP; NADPH
______ plants only uptake CO2 at night because they close their ______ during the day.
Cam; stomata
Which are the two most important kinds of pigments in chloroplasts?
Chlorophylls and carotenoids
Which of the following statements best describes the properties of light?
Light has properties of both a particle and a wave.
Which of the following accurately describes C4 photosynthesis?
PEP is synthesized in the mesophyll cells, while the Calvin cycle occurs in the bundle-sheath cells.
Which photosystem's main function is to generate high-energy electrons for the synthesis of ATP?
Photosystem 2
In the Calvin cycle CO2 is attached to an organic molecule abbreviated as
RuBP
Which of the following statements about radiation is TRUE?
Shorter-wavelength radiation carries more energy per unit of time than longer-wavelength radiation.
The _________ membrane of the chloroplast contains pigment molecules, including chlorophyll.
Thylakoid
A photon of light has properties of both
particle and wave
The energy used by most living cells comes ultimately from the _________ and is captured through the process of ________
sun; photosynthesis
Plants that use _______ photosynthesis avoid water loss by closing their stomata during the day and opening them at night.
CAM
How do CAM plants avoid water loss?
CAM plants close their stomata during the day and open them at night
How are the C3 and the C4 pathways separated in CAM plants?
The C4 pathway occurs at night, while the C3 pathway occurs during the day.
In the Fall, aspen leaves change from a green color to a lovely yellow color. Seasonal color changes in a leaf happen because ______.
The quantity of chlorophyll in a leaf declines, unmasking the carotenoids
Which of the following membranes contains pigments in a green plant?
The thylakoid membrane
How are the equation for photosynthesis in plants and the equation for cellular respiration related?
They are the reverse of each other
Which of the following happens to the molecule formed by the addition of carbon dioxide to ribulose bisphosphate?
It is immediately split into two more stable three carbon molecules (PGA).
Photorespiration has which of the following effects on photosynthesis?
It reduces the yield of photosynthesis.
Which of the following statements about the oxidation potential of photosystem II is true?
Its oxidation potential is high enough that it can oxidize water.
Which of the following is the primary output of the Calvin cycle?
G3P
The oxygen produced by plants during photosynthesis comes from the splitting of ________ molecules.
H2O
