bio ch 8 & 9
Place the four stages of the thylakoid reactions in the correct order starting with the first stage at the top.
1. primary photoevent 2. charge separation 3. electron transport 4. chemiosmosis
Consider the net equation that describes the Calvin cycle. How many NADPH are needed to synthesize the two net G3P molecules that can be used to make a glucose molecule?
12
How many different types of photosystems are found in chloroplasts?
2
How many types of photosystems are found in chloroplasts?
2
Typically, it is considered that the net gain of the Calvin cycle is(are) ________ molecule(s) of G3P.
2
How many molecules of CO2 need to be bound to molecules of RuBP to produce 12 molecules of PGA in the Calvin cycle?
6
In the Calvin cycle, _______ molecules of CO2 are bound to the same number of RuBP molecules to produce 12 molecules of PGA.
6
Which of the following are parts of a chlorophyll molecule?
A porphyrin ring A hydrocarbon tail
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
How does the structure of chlorophyll enable its photosynthetic function?
An electron can be delocalized across the porphyrin ring, allowing it to absorb energy.
Which of the following organisms have only one photosystem?
Anoxygenic bacteria
Why is the Calvin cycle also known as C3 photosynthesis?
Because the first molecule in the cycle has 3 carbon atoms.
According to the generalized equation for photosynthesis proposed by van Niel, CO2 + 2H2A + light energy yields which of the following?
CH2O + H2O + 2A
What molecule is released during photorespiration?
Carbon dioxide
Oxygenic photosynthesis is found in cyanobacteria, seven groups of algae, and essentially all land plants.
Carbon fixation involves using the protons and electrons generated by the splitting of what molecule to convert CO2 into organic matter?
Which of the following pairs is matched incorrectly?
Chlorophyll b:main photosynthetic pigment in plants.
What is transferred out of the reaction center?
Excited electrons.
Which photosystem's main function is to generate high-energy electrons for the synthesis of ATP?
Photosystem II
Which of the following are phases of the Calvin cycle?
Regeneration of ribulose bisphosphate Carbon fixation Reduction and carbohydrate production
What is ultimately the main source of energy for almost all living cells on Earth?
The Sun
True or false: Glucose is the primary output of the Calvin cycle.
The primary output of the Calvin Cycle is G3P. Two molecules of G3P can then be used to make glucose.
Which of these statements are true about the relationship between photosynthesis and cell respiration?
The products of cell respiration are the reactants of photosynthesis. The products of photosynthesis are the reactants of cell respiration.
Which of the following is an accurate description of carotenoids?
They are made of carbon rings connected to carbon chains with alternating single and double bonds.
The production of one molecule of O2 during photosynthesis requires how many chlorophyll molecules?
Thousands
A photon of light has properties of both
a particle and a wave.
Chlorophyll _______ is the main photosynthetic pigment in plants as it converts light energy into chemical energy; chlorophyll _______ acts as an accessory pigment.
a; b
In plants, each photosystem is a network of chlorophyll ________ molecules, accessory ______ and associated proteins.
a; pigments
A graph depicting the efficiency of photon absorption by a pigment molecule as a function of photon wavelength is known as the
absorption spectrum of the pigment
Photophosphorylation produces _________, which stores chemical energy that can be used for the Calvin cycle. Carbon fixation also requires reducing power, which is provided by __________ produced by photosystem I.
atp; nadph
The ATP needed in the Calvin cycle comes from
both cyclic and noncyclic photophosphorylation
The light-_______ reactions of photosynthesis occur on membranes.
dependent
In the reaction center, excited _______ (is)are transferred out of the photosystem.
electrons
In the visible spectrum, light energy may be absorbed by boosting _______ to higher atomic energy levels, sometimes called energy shells.
electrons
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
The ATP synthases of chloroplasts and mitochondria are
evolutionary related
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
True or false: The light-dependent reactions of photosynthesizing bacteria take place in the chloroplasts.
false, bacteria do not have chloroplasts
The process in which electrons from water move through PSII and PSI and ultimately to NADPH is also known as ________ photophosphorylation.
noncyclic
In chloroplasts, electrons ejected from the photosystems do not return to them, which is known as
noncyclic photophosphorylation.
Anoxygenic bacteria have how many photosystems?
one
For an electron to absorb light energy, it must absorb a(n) ________ that contains enough energy to overcome the energy difference between the orbital the electron is in, and the one to which it will be boosted.
photon
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
In all photosynthetic organisms studied to date, except one class of photosynthetic bacteria, light is captured by clusters of chlorophyll and accessory pigment molecules, which together are called
photosystems
Almost all photosynthetic organisms capture light using
photosystems.
In a chlorophyll molecule, an excited electron can follow a path around several atoms in the ______ ring, meaning it is delocalized, and thus able to absorb light energy.
porphyrin
Recent studies with the atomic force microscope have shown that PSI and the ATP synthase are not randomly distributed in thylakoid membranes, rather, they seem concentrated
primarily in the connections between grana (the stroma lamellae).
The first stage of the thylakoid (or light-dependent) reactions is the
primary photoevent
The reaction center in chloroplasts is a transmembrane ________pigment complex.
protein
In a photosystem, chlorophyll a molecules are found in a matrix of
proteins
A leaf that appears to be green to the human eye contains pigment molecules that are
reflecting green light
The range and efficiency of photons that a pigment molecule is capable of absorbing constitute its characteristic absorption
spectrum
When photosynthesis results in the accumulation of G3P in the stroma faster, the G3P is used to make glucose 1-P which is then used to make
starch grains
During times of intensive photosynthesis, chloroplast can store glucose in the form of
starch grains.
In hot, arid conditions, specialized openings in the leaf called ________ close to conserve water, cutting off the supply of carbon dioxide entering the leaf.
stomata
Most plants transport the fixed carbon in the form of the transport sugar
sucrose
Once a photon is captured by the light harvesting complex, the pigments in it transfer
the energy of excited electrons but not electrons themselves.
In bacteria, light-dependent reactions take place in which of the following?
the plasma membrane
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.
The inner (internal) membrane of the chloroplast is also called the ________ membrane.
thylakoid
The internal membrane of the chloroplast is also known as the
thylakoid membrane.
Jan Baptista _____ _______performed an experiment for which he grew a willow tree in a pot for several years, during which time he kept an exact record of changes in the weight of the soil.
van helmont
Which of the following wavelengths of light are preferentially absorbed by chlorophyll molecules?
violet blue and red
How is the reaction center positioned in the membrane?
It is a transmembrane complex.
Which of the following represent the phases of the Calvin cycle?
(1) carbon fixation; (2) reduction and carbohydrate production; (3) regeneration of ribulose bisphosphate
Which of the following is the primary output of the Calvin cycle?
G3P
Glyceraldehyde 3-phosphate formed during the Calvin cycle is an important compound in which of the following stages of cell respiration?
Glycolysis
In van Niel's generalized equation of photosynthesis, which of the following is the donor of electrons?
H2A
Carbon fixation involves using the protons and electrons generated by the splitting of what molecule to convert CO2 into organic matter?
H2O
Which of the following describes van Helmont's experiment?
He grew a willow in a pot keeping an exact record of the weight of the soil and the tree over several years.
When you take into account the net equation of the Calvin cycle, how many ATP molecules are needed to synthesize two G3P molecules?
In order to produce 2 G3P molecules in the Calvin cycle, 12 molecules of NADPH are needed, as well as 18 molecules of ATP.
According to recent studies, where are PSII and the b6-f complexes located?
In the grana and in borders between the grana and the stroma lamellae
Where do the light-dependent reactions of photosynthesis occur in the chloroplast?
In the thylakoid membrane.
Plants that only fix carbon using the Calvin cycle are also known as __________ plants
c3
The Calvin cycle is also known as _______ photosynthesis because the first intermediate of the cycle contains three carbon atoms.
c3
van Niel introduced the term ______ _______ to denote the process of converting CO2into organic matter using the electrons and protons resulting from the splitting of water.
carbon fixation
________ are accessory photosynthetic pigments that consist of carbon rings linked to chains with alternating single and double bonds.
carotendoids
The two most important classes of pigments in chloroplasts are chlorophylls and
carotenoids
______are accessory photosynthetic pigments that consist of carbon rings linked to chains with alternating single and double bonds.
carotenoids
In photosynthesis, ________ molecules preferentially absorb violet-blue and red light.
chlorophyll
