Photosynthesis quizlet
pigment molecules bound to protein
light-harvesting complexes
transfer the energy of photons to the reaction center
light-harvesting complexes
the primary pathway that involves both photosystems and produces ATP and NADPH using light energy
linear electron flow
you see the _____ of visible light
medium
photolysis occurs __, and uses _____ nanometers (PS_)
once, 680, II
a ______ is a collection of pigment
photosystem
endergonic, or
powered by light
The reactions that occur in the thylakoid membranes are:
the light-dependent reactions
where do light reactions occur?
the thylakoid membrane
connected sacs in the chloroplast, contain a third membrane system
thylakoid
Oxygen produced by the light reactions of photosynthesis comes directly from:
H2O
light reactions split _____ and release O2 into the
H2O, atmosphere
reducing enzyme
NADP+ reductase
All organisms are classified into two general trophic groups. These two groups are:
autotrophs and heterotrophs
thylakoids may be stacked in columns called
grana
What is the correct order of the main steps of ATP synthesis in the light-dependent reactions of photosynthesis?
light excites electrons in photosystem II, electrons from photosystem II pass along electrons transport chain, carriers use energy from electrons to move H+ across membrane, H+ concentration gradient established, H+ diffuses through a transport protein, energy of H+ flow and ATP synthetase make ATP
light reactions convert ____ energy to the ____ energy of ____ and _____
light, chemical, ATP, NADPH
All of the following statements are true regarding the Calvin Cycle of photosynthesis except: a. the energy source utilized is ATP and NADPH b. these reactions begin after sundown and begin before sunrise c. the five carbon sugar RuBP is constantly being regenerated d. the intermediate product is PGAL e. the reactions are all enzyme mediated
b.
In the overall reactions of photosynthesis, it appears that hydrogen atoms are transferred from water to carbon dioxide to form a carbohydrate. This type of reaction is classified as:
a redox reaction
Which of the following is not one of the intermediates or products of the carbon fixation reactions? a. NADPH b. PGA c. PGAL d. glucose e. RuBP
a.
Which term is NOT correctly matched with the appropriate energy source or carbon source? a. heterotroph--light energy sources b. chemotroph--chemical energy sources c. phototroph--light energy sources d. autotroph--carbon fixation
a.
what do pigments do?
absorb light?
Which of the following is not associated with the thylakoid membrane? a. photosystems I and II b. the Calvin Cycle c. electron transport chain d. ATP synthase e. cytochrome complex
b.
weak medium example
microwaves
what is the process called when the photon from PSII split the water molecule?
photolysis
where do the electrons come from that replace the first two that left the chlorophyll a molecule?
photolysis
a small packet of light is called a
photon
Light behaves not only as waves, but also as particles, which are referred to as:
photons
light behaves as though it consists of discrete particles called
photons
in _____, rubisco adds ____ instead of CO2 in the calvin cycle, producing a ____ - carbon compound
photorespiration, O2, 2
The process by which light energy is converted into the stored chemical energy of organic molecules is:
photosynthesis
cyclic electron flow uses ____ and produces _____, but not ______
photosystem I, ATP, NADPH
functions first and uses chlorophyll a
photosystem II 680 nanometers
in the reaction center, this accepts excited electrons and is reduced as a reulst
primary electron acceptor
Plants, algae, and certain bacteria are:
producers
a hydrogen atom that has lost its electron is called a
proton
what kind of pump is found in the membrane of light reactions?
proton pump
a photosystem has a type of protein complex called
reaction-center complex
The energy of a photon light is least for ________ light.
red
Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on what process?
synthesis of ATP
What is the primary function of the Calvin Cycle?
synthesize simple sugars from carbon dioxide
what is the most important molecule in the light reactions?
water
the distance between crests of waves; determines the type of electromagnetic energy
wavelength
the higher the frequency the ______ the wave
weaker
ROYGIBIV
weakest to strongest as the colors go across
strong medium example
x-rays
is oxygen released in photolysis?
yes
in what part of the chloroplast do you find the enzymes needed for photosynthesis?
stroma
how many PGAL's are needed to make one glucose molecule? how many times does the cycle spin?
2, twice
photolysis
2H2O--->4H^+ + 4e- + O2
it takes _______ to turn __ PGAL and __ RuBp into __ PGAL and __ RuBp
3 ADP, 5, 3, 3, 5
____H2O/glucose
6
the calvin cycle needs _____ nanometers to start
680
photosynthesis
6CO2+ 6H2O -----> (sunlight) C6H12O6 + 6O2
what wavelength does chlorophyll b absorb?
700 nanometers
the calvin cylce returns ____, ______, and ______ to the light reactions
ADP, inorganic phosphate, and NADP+
Thylakoid membranes are involved in ____________ synthesis.
ATP
what is the name of the enzyme that combines with the energy from the electrons to form the product of the light reactions?
ATP synthase
what is the name of the channel that the protons pass through in light reactions?
ATP synthesizing channel
the calvin cycle uses ____ and ____ to make ____ into the sugar ______
ATP, NADPH, CO2, G3P
photorespiration consumes O2 and releases CO2 without producing ____ or ____
ATP, sugar
some plants, including succulents, use ______ to fix carbon
CAM
the closing of stomata reduces access to ____ and causes ____ to build up
CO2, O2
1 molecule of PGAL is spit out during the calvin cycle after ________ is made
GAP dehydrogenase
___ is oxidized and ____ is reduced in photosynthesis
H20, CO2
Noncyclic electron transport needs a constant supply of electrons. These are obtained from:
H2O
some substances, such as purple sulfur bacteria, have PS _ but not PS _
I, II
give the name of the reducing protein found in the thylakoid membrane.
NADP+
what is the name of the final electron acceptor for the light reactions?
NADP+
what are the products of light reactions?
NADPH and ATP
what is the name of the final electron acceptor in the cytochrome a complex?
PC
where does the energy come from to run the pump?
PC
Ribulose phosphate is synthesized from:
PGAL
______ is the intermediate molecule formed in the calvin cycle
PGAL
G3P is another name for
PGAl
A spaceship is designed to support animal life for a multilayer voyage to the outer planets of the solar system. Plants will be grown to provide oxygen and to recycle carbon dioxide. Since the spaceship will be too far from the sun for photosynthesis, an artificial light source will be needed. What wavelengths of light should be used to maximize plant growth with a minimum of energy expenditure?
blue and red light
the calvin cycle begins with ______, incorporating _____ into organic molecules
carbon fixation, CO2
the calvin cycle has three phases
carbon fixation, catalyzed by rubisco, reduction, and regeneration of the CO2 acceptor RuBp
an accessory pigment is called a
carotenoid
In autumn, the leaves of deciduous trees change colors. This is because chlorophyll is degraded and _____________________________.
carotenoids and other pigment are still present in the leaves
where does the plant get the water for photosynthesis if there is no rain water available?
central vacuole
when ATP breaks off a phosphorous group and turns itself into ADP, which then picks up a phosphorous group to become ATP
chemiosmosis
pigment that gives leaves their green color
chlorophyll
The most important photosynthetic pigment is:
chlorophyll a
the pigment/ reaction center for PSII is
chlorophyll a
As a research scientist, you measure the amount of ATP and NADPH consumed by the Calvin Cycle in one hour. You find that 30,000 molecules of ATP were consumed, but only 20,000 molecules of NADPH were consumed. Where did the extra ATP molecules come from?
cyclic electron flow
in this, electrons flow back from ferredoxin to the photosystem I reaction
cyclic electron flow
ATP is _______ to make ADP
dephosphorylized
carbon fixation does or does not need energy?
does not
Which of these colors contributes the least energy to photosynthesis? a. blue b. red c. violet d. orange e. green
e.
when the excited electrons leave the chlorophyll a molecule, they enter a membrane potential called the
electron transport chain
photosynthesis is a(n) _____ process
endergonic
The synthesis of ATP as a result of the light-dependent reactions of photosynthesis is an _____________ reaction that is couple to the diffusion of ___________ down their concentration gradient.
endergonic; protons
NADP+ reductase is an _____ and a _______
enzyme, final electron acceptor
True or False: The electrons that leave the electron transport system have just as much energy as when they went in
false
what is the name of the primary electron acceptor in light reactions?
ferredoxin
number of waves in a given space
frequency, measured in apmtitudes or ampts
What chemical has the most energy in the Calvin Cycle?
glucose
ATP is formed when ___________ the thylakoid lumen.
hydrogen ions leave
What is chlorophyll's reaction to light?
it absorbs red and blue light, and reflects green light
An electron absorbs a photon of light energy and becomes energized; the electron shifts from a ______________ atomic orbital to a _____________ atomic orbital.
low energy; high energy
You have just discovered a new flower species that has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths are not being absorbed by this pigment?
red and yellow
NADP+ is a
reducing protein
we see the color that is
reflected
In the process of carbon fixation, RuBP attaches a carbon dioxide to produce a six carbon molecule, which is then split to produce two molecules of PGA. After phosphorylation and reduction produces PGAL what needs to happen to complete the Calvin Cycle?
regeneration of RuBP
kinase means to
remove and attatch a phosphate group
_____ is the most abundant
rubisco
what are the electrons called that enter photosystem I?
spent electrons
CO2 enters and O2 exits through pores called
stomata
In C3 plants, the ______________ are typically closed at night and open during the daytime to allow for gas exchange.
stomata
In a chloroplast, there is an outer and an inner membrane. The inner membrane encloses a fluid-filled region called the:
stroma
defense fluid
stroma
PGAL is the _____ formed in the calvin cycle
the intermediate molecule
chlorophyll a and chlorophyll b absorb different wavelengths of light because
they are making different kinds of energy