BIO 201 UNCW Chapter 8 Brooker
Which of the following is the source of electrons used to ultimately reduce the C-O bond of PGA? G3P ATP NADPH Rubisco
NADPH
Which of the following is the source of electrons used to ultimately reduce the C-O bond of PGA? rubisco G3p NADPH ATP
NADPH
The oxidation of _____ is important in replenishing electrons in P680 after electrons are lost by excitation.
water
Green plants uptake two vital reactants of photosynthesis through their roots and stomata, respectively. What are these reactants?
water and carbon dioxide
Electromagnetic radiation travels as ____ caused by the oscillation of the electric and magnetic fields.
waves
Electromagnetic radiation travels as: waves fields particles rays
waves
Which of the following produce ATP that could be used in phase 3 of the Calvin cycle? a. the light reactions b. ATP synthases in the thylakoid membrane c. phase 1 of the Calvin cycle d. Photosystem I e. cyclic electron flow
a, b, e
The two-step process of photosynthesis is conserved across: heliobacteria algae actinobacteria green plants cyanobacteria fungi
algae, green plants, cyanobacteria
When a high energy electron is transferred from P680 to the primary electron acceptor: a. ATP is generated b. solar energy is "captured" to do work c. the reaction center is excited d. NADPH is generated
b
Carbohydrates are very important to plant cells because they: a. are structurally reactive and can establish an electrochemical gradient b. can be used as an energy reserve c. are implicated in the formation of "biological batteries" d. form the building blocks for many organic macromolecules
b & d
How might a reaction that requires an input of energy proceed? a. by allowing it to occur under spontaneous circumstances b. by coupling it to a spontaneous reaction c. by coupling it to an exergonic reaction d. by coupling it to an endergonic reaction
b, c
Which of the following are membranes found in a chloroplast? an inner membrane the lumen membrane the thylakoid membrane the outer membrane the stroma membrane
inner membrane thylakoid membrane outer membrane
The word "photosynthesis," "photo" refers to the ___ reactions, in which light energy is captures, while "synthesis" refers to the synthesis of _____ in the Calvin cylce.
light carbohydrates
The light reactions convert ___ energy into ____ energy stores in covalent bonds.
light chemical
If an excited electron return to its original energy shell within the same atom, the electromagnetic energy originally used to excite the electron may be released as: light electrical energy heat
light heat
Rather than releasing energy, an excited electron in a photosynthetic pigment is removed from that molecule and transferred to another molecule where the electron is _____ stable.
more
The flow of electrons from PSII to PSI is called _____ electron flow because electrons end up at different destinations.
noncyclic
In the following generalized equation for photosynthesis, what does "A" represent for photosynthesis in green plants? carbohydrates sunlight water oxygen carbon dioxide
oxygen
Which of the following molecules is produced by photosystem II? light oxygen sugar water carbon dioxide
oxygen
Light has properties of both a _____ and a ____.
particle wave
During photosynthesis, NADPH is synthesized by: the Calvin cycle PSII PSI ATP synthase
photosystem I
When a ____ molecule absorbs a photon of light, an electron is boosted to a higher energy level.
pigment
Carotenoids are _____ membranous structures in a chloroplast photosystems pigments gas exchange structures chlorophyll variants
pigments
The pores in the surface of a leaf that can participate in gas exchange are called ____.
stomata
The fluid-filled region of the chloroplast between the thylakoid membrane and the inner membrane is called: the granum the thylakoid lumen the stroma the intermembrane space
stroma
Photosystems I and II are located in: the stroma the inner mitochondrial membrane the thylakoid membrane the intermembrane space
the thylakoid membrane
The ____ membrane contains pigment molecules, including chlorophyll.
thylakoid
The light-harvesting complex is found in the ____ membrane.
thylakoid
A granum is a stack of ___ .
thylakoids
When a photon of light with the correct amount of energy strikes an electron, it is boosted from a(n) _____ state to a photoexcited state.
unexcited
In photosynthesis, ____ is produced via the reduction of CO2.
glucose
The wavelength of visible light is between: 1-100 nm 545-833 nm single wavelength 380-740 nm invisible and visible light
380-740 nm
A key bond change in the reduction phase of the Calvin cycle in the reduction of the C-____ bond to a C-____ bond.
C-O to a C-hydrogen
Ninety percent of the plants of Earth are: CAM plants C4 plants C3 plants
C3 plants
Which of the following would be an appropriate radioactive tracer for studying the flow of carbon through the Calvin cycle? radioactive ATP radioactive sulfur radioactive CO2 radioactive glucose
CO2
In the first phase of the ___ cycle, atmospheric carbon dioxide is fixed into a five carbon sugar.
Calvin
T/F: The term "C3" was derived from the 3-carbon sugar that represents the end product of photosynthesis.
False
During photosynthesis, NADPH is synthesized by: PSI ATP synthase the Calvin cylce PSII
PSI
Why might plants contain a variety of pigments? a. because each pigment is necessary to generate an electromagnetic spectrum b. because each pigment is ultimately the final electron acceptor for its own ETC c. because this feature enables plants to absorb light at many different wavelengths d. because visible light contains only one wavelength on a seasonal basis
c
Which of the following are components of both PSI and PSII? a. NADP+ reductase b. an ATP synthase c. a reaction center d. a light harvesting complex
c d
____ plants only uptake co2 at night because they close their ___ during the day.
cAM stomata
The _____ generated in the Calvin cycle are synthesized using carbon dioxide from the atmosphere.
carbohydrates
The G3P produced at the end of phase 2 of the Calvin cycle is used to synthesize ____ and to regenerate the molecule ____ _____.
carbohydrates ribulose bisphosphate
In a carbon dioxide molecule, why are carbon atoms considered to be "electron poor" while oxygen atoms are "electron rich"? a. because electrons are not limited to atmospheric molecules b. because carbon dioxide is a polar molecule c. carbon is a very electronegative atom d. oxygen is a very electronegative atom
d
Light is considered a form of electromagnetic radiation because: a. it responds to magnetic stimuli b. light and magnetic waves can bend c. it is polarized d. it consists of both electric and magnetic energy
d
When a pigment molecule absorbs a photon of light: a. carbohydrates are synthesized b. reducing power is generated c. water is oxidized d. an electron is boosted to a higher level e. electrons in photosystem II are replenished
d
Electrons in an _____ state tend to be unstable, and thus must release or channel their energy.
excited
T/F A molecule that loses an electron is reduced.
false
After ____ molecules are made, they may be linked together in a polysaccharide called starch.
glucose
In the process of photosynthesis, water is oxidized during the formation of ____ .
O2
The role of the reaction center in PSII is to quickly remove the high energy electron from ____ and transfer it to another molecule where it will be more stable.
P680
Carbon dioxide is reduced during the formation of ____ .
G3P
Why is it significant that energy from excited electrons in photosynthesis is "captured"? a. because the energy is not released but instead used productively b. because the energy is actually in the form of carbohydrate c. because "captured" energy is released as light, which is used to excited other electrons d. because "captured" energy is released as heat, which is the basis of endothermy
A
P680 replenishes its high energy electron via a low energy electron that the reaction center extracts from ____ .
H20
Match the terms to their outcome in the generalized equation for photosynthesis: H2A - oxidized/reduced CO2 - oxidized/reduced
H2A - oxidized CO2 - reduced
Which of the following are major outputs of the light reactions? NADPH carbohydrates ATP NADP photons
NADPH ATP
The G3P produced at the end of the second phase of the Calvin cycle is directly used to: a. regenerate ribulose bisphosphate b. make glucose or other carbohydrates c. donate low energy electrons d. produce ATP e. reduce NADP+
a
Wavelengths refers to: a. the distance between the peaks in a wave pattern b. the depth between peaks in a wave pattern c. the height of peaks in a wave pattern d. the number of peaks in a wave pattern e. the length of the ascending portion of a waveform
a
Which of the following are examples of redox reactions that occur during photosynthesis? A. The removal of low energy electrons from water B. The generation of NADPH C. The transfer of high-energy electrons from a pigment molecule to the primary electron acceptor D. The excitement of an electrons
a b c
The function of both NAD+ in cellular respiration, and NADP+ in photosynthesis, are similar in that they both act as: a. an oxidizing agent b. an electron carrier that can accept two electrons c. a reducing agent d. a photosystem adapted to capture light
a, b
Which of the following explain why a 3 carbon molecule is reduced to another 3 carbon molecule in phase 2 of the Calvin cycle? a. because G3P can polymerize more easily b. because the bonds of G3P store more energy c. because the bonds in 3GP release energy when broken d. because the latter 3 carbon molecule is an enzyme
a, b
How is an H+ electrochemical gradient established and maintained in photosynthesis? a. the movement of electrons from PSII to PSI b. the formation of NADPH c. the splitting of water d. the reduction of carbon dioxide e. the formation of carbohydrates f. the movement of electrons from PSi and PSII
a, b, c
Ultraviolet light is more damaging to cells than visible light because: a. UV light is higher energy than visible light b. UV light is less abundant than visible light c. UV light has a shorter wavelength than visible light d. visible light is not absorbed by most cells, while UV light is
a, c
Which of the following produce ATP that could be used in phase 3 of the Calvin cycle? a. cyclic electron flow b. phase 1 of the Calvin cycle c. ATP synthases in the thylakoid membrane d. photosystem I e. the light reactions
a, c, e
Why does CO2 enter CAM plants at nighttime? a. because CAM plants contain only mesophyll cells b. because CAM plants fix carbon dioxide before it enters the leaf during the day c. because the stomata of CAM plants are only open at night d. because CAM plants photosynthesize at night
c
Carbon atoms found in the sugars made in photosynthesis are ultimately incorporated from ____ ____ molecules from the atmosphere.
carbon dioxide
In the light reactions, ATP is generated via: the direct excitation of electrons chemiosmosis glycolysis the Calvin cycle
chemiosmosis
Which of the following are used by green plants to absorb light energy? chlorophyll b chlorophyll c xanthophyll b chloroplast c chlorophyll a
chlorophyll a & b
In plants, which of the following is polymerized to form starch? glyceraldehyde-3-phosphate sucrose ribulose biphosphate glucose
glucose
Organisms that acquire energy by consuming organic molecules from environment are called _____.
heterotrophs
The enzyme rubisco has more than one activities. Because of this, most plants also perform _____, which consumes oxygen and liberates carbon dioxide. This process can lower the net benefit from photosynthesis.
photorespiration
The process by which plants capture light energy and use it to synthesize carbohydrates is called _____.
photosynthesis
Carotenoids are: membranous structures in a chloroplast pigments gas exchange structures chlorophyll variants photosystems
pigments
Several dozen of these kinds of molecules help comprise a light harvesting complex: ETCs manganese clusters pigments NADP+ reductases ATP synthases
pigments
The energy that is released as electrons pass from one electron carrier to the next is used to pump ____ into the thylakoid lumen.
protons
Which of the following are components of both PSI and PSII? an ATP synthase a reaction center a light harvesting complex NADP+ reductase
reaction center light harvesting complex
In a typical redox reaction, a molecule that becomes _____ is known as the oxidiing agent because it receives one or more ____ from another molecule.
reduced electrons
In photosynthesis, glucose is produced via the ____ of CO2.
reduction
Gamma rays and radio waves represent two extreme sets of wavelengths on this sale of radiation: the electromagnetic spectrum a gamma-radiographic assembly the visible spectrum the radiation index
the electromagnetic spectrum
