BIOl 1100 ch. 8 test review
In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules? 3 1 5 2 4
3
According to the chemiosmotic hypothesis, what provides the energy that directly drives ATP synthesis? View Available Hint(s) Osmotic gradient Temperature gradient Proton gradient Electrons
proton gradient
After 3-PGA is phosphorylated, it is reduced by _____. ATP CO2 NADPH NADP+ ADP
NADPH
What compound provides the reducing power for the Calvin cycle reactions? ATP CO2 NADPH FADH2 FAD
NADPH
Which of the following molecules is the primary product of photosystem I? View Available Hint(s) Carbon dioxide Oxygen NADPH ATP
NADPH
Which of the following products of the light reactions of photosynthesis is used during the Calvin cycle? sugar NADPH oxygen ADP + Pi water
NADPH
why so?
Oxygen is a by-product of the photosynthetic process.
Which term describes ATP production resulting from the capture of light energy by chlorophyll? View Available Hint(s) Dephosphorylation Photophosphorylation Oxidative phosphorylation Substrate-level phosphorylation
Photophosphorylation
Part complete Which of the following particles can pass through the ATP synthase channel? View Available Hint(s) ATP ADP Inorganic phosphate Protons
protons
Which of the following is directly associated with photosystem I? extraction of hydrogen electrons from the splitting of water harvesting of light energy by ATP receiving electrons from the thylakoid membrane electron transport chain generation of molecular oxygen
receiving electrons from the thylakoid membrane electron transport chain.
Which of the following does NOT occur during the Calvin cycle? regeneration of the CO2 acceptor carbon fixation release of oxygen oxidation of NADPH
release of oxygen
In the process of carbon fixation, three molecules of RuBP combine with three molecules of CO2 to produce three six-carbon molecules, which are then split to produce 12 molecules of 3-phosphoglycerate. After phosphorylation and reduction produce 12 glyceraldehyde 3-phosphate (G3P), what more needs to happen to complete the Calvin cycle? release of two G3P to make sugars and regeneration of RuBP release of one G3P to make sugars and regeneration of RuBP release of one G3P to make sugars and regeneration of citrate release of one G3P to make sugars and regeneration of NADPH release of two G3P to make sugars and regeneration of ATP from ADP
release one G3P to make sugars and regeneration of RuBP
C4 plants differ from C3 and CAM plants in that C4 plants _____. use PEP carboxylase to fix carbon dioxide are better adapted to wet conditions transfer fixed carbon dioxide to cells in which the Calvin cycle occurs use malic acid to transfer carbon dioxide to the Calvin cycle open their stomata only at night
transfer fixed carbon dioxide to cells in which the Calvin cycle occurs
Which process produces oxygen? Photosynthesis Cellular respiration
photosynthesis
Why are plants classified as producers? Plants are classified as producers because they are at the bottom of the food chain. Plants are classified as producers because they fix inorganic carbon into organic molecules. Plants are classified as producers because they produce oxygen.
plants are classified as producers because they fix inorganic carbon into organic molecules
True or false? The chemiosmotic hypothesis states that the synthesis of ATP generates a proton gradient that leads to electron flow through an electron transport chain. true False
false
True or false? The region of ATP synthase that catalyzes the production of ATP from ADP and inorganic phosphate spans the chloroplast membrane. True False
false
In a plant cell, where are ATP synthase complexes located? thylakoid membranes only thylakoid membrane and plasma membranes plasma membrane only inner mitochondrial membranes only thylakoid membrane and inner mitochondrial membranes
thylakoid membrane and inner mitochodrial membranes
Where are the molecules of the electron transport chain associated with photophosphorylation located in plant cells? inner membrane of mitochondria matrix of mitochondria stroma of chloroplasts outer membrane of chloroplasts thylakoid membranes of chloroplasts
thylakoid membranes of chloroplasts
In the thylakoid membranes, what is the main role of the pigment molecules in a light-harvesting complex? split water and release oxygen to the reaction-center chlorophyll transfer light energy to the reaction-center chlorophyll transfer electrons to NADPH synthesize ATP from ADP and ℗i
transfer light energy to the reaction-center chlorophyll
True or false? The light-dependent reactions of photosynthesis use water and produce oxygen. True False
true
Which of the following statements is a correct distinction between autotrophs and heterotrophs? Cellular respiration is unique to heterotrophs. Only heterotrophs have mitochondria. Only heterotrophs require chemical compounds from the environment. Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic.
autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic
Generation of proton gradients across membranes occurs during cellular respiration only. photosynthesis only. both photosynthesis and cellular respiration. neither photosynthesis nor cellular respiration.
both photosynthesis and cellular respiration
In C4 and CAM plants carbon dioxide is fixed in the _____ of mesophyll cells. grana stomata cytoplasm stroma thylakoids
cytoplasm
How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose? 10 6 8 2 4
6
Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle? ATP and NADPH ADP, i, and NADP+ H2O and O2 electrons and H+ CO2 and glucose
ATP and NADPH
Which of the following events occurs in the light reactions of photosynthesis? Carbon dioxide is fixed in organic molecules. ATP is consumed to yield ADP. Light is absorbed and funneled to reaction-center chlorophyll a. NADP+ is produced.
light is absorbed and funneled to reaction-center chlorophyll a.
The overall function of the Calvin cycle is __________. splitting water producing carbon dioxide making sugar capturing sunlight oxidizing glucose
making sugar
The splitting of carbon dioxide to form oxygen gas and carbon compounds occurs during both photosynthesis and cellular respiration. neither photosynthesis nor respiration. photorespiration. respiration. photosynthesis.
neither photosynthesis and cellular respiration
Photosynthesis is a redox reaction. This means that H2O is _____ during the light reactions and CO2 is _____ during the Calvin cycle. View Available Hint(s) consumed...reduced oxidized...reduced reduced...oxidized consumed...consumed reduced...reduced
oxidized....reduced
Where does the Calvin cycle take place? stroma of the chloroplast thylakoid membrane outer membrane of the chloroplast interior of the thylakoid (thylakoid space
stroma of the chloroplast
The ultimate source of energy to support most life on Earth is _____. geothermal heat sunlight photosynthetic plants the carbon cycle chemosynthetic microbes
sunlight
NADP superscript plus sign, ADP, and H2O react in light reactions in the presence of light to produce ATP, NADPH, and O2. ATP, NADPH, and CO2 are used in the Calvin Cycle to produce ADP, NADP superscript plus sign, and sugar made of CH2O monomers. Select the most accurate statement describing the basic function of the light reactions of photosynthesis. The basic function of the light reactions of photosynthesis is the trapping of light energy. The basic function of the light reactions of photosynthesis is the conversion of solar energy to chemical energy. The basic function of the light reactions of photosynthesis is the production of glucose.
the basic function of the light reactions of photosynthesis is the conversion of solar energy to chemical energy
Which set of reactions uses H2O and produces O2? The light-dependent reactions The light-independent reactions
the light-dependent reactions
Which of the following sequences correctly represents the flow of electrons during photosynthesis? NADPH → O2 → CO2 H2O → photosystem I → photosystem II H2O → NADPH → Calvin cycle NADPH → electron transport chain → O2
C.
Select the correct molecule that is the main product of the Calvin cycle. NADPH G3P Glucose
G3P
what do photoautotrophs do
Photoautotrophs use light as a source of energy to synthesize organic substances.
Carbon fixation involves the addition of carbon dioxide to _____. RuBP 3-PGA G3P NADPH Rubisco
RuBP
Which molecule is regenerated in the regeneration phase of the Calvin cycle? Without regeneration of this molecule, the Calvin cycle would stop. 3-phosphoglycerate G3P RuBP ATP
RuBP
a fact
Six carbon dioxide molecules are required to produce two G3P molecules, which can be combined to make one glucose molecule.
Compared to C3 plants, C4 plants can continue to fix CO2 even at relatively low CO2 concentrations and high oxygen concentrations. grow better under cool, moist conditions. do not use rubisco for carbon fixation. have higher rates of photorespiration.
can continue to fix CO2 even at relatively low CO2 concentrations and high oxygen concentrations.
Which of the following statements about the relationship between photosynthesis and cellular respiration is true? In cellular respiration the biochemical pathways of photosynthesis run in reverse. Cellular respiration occurs only in animals and photosynthesis occurs only in plants. There is a net consumption of ATP in cellular respiration and a net production of ATP in photosynthesis. In photosynthesis the biochemical pathways of cellular respiration run in reverse. Cellular respiration is catabolic and photosynthesis is anabolic.
cellular respiration is catabolic and photosynthesis is anabolic
In C3 plants the conservation of water promotes _____. photorespiration a shift to C4 photosynthesis the light reactions the opening of stomata photosynthesis
photorespiration
What contains chlorophyll?
the photostems
_____ splits water into 1/2 O2, H+, and e- . The figure shows the membrane of the thylakoid. Letters from A to E indicate definite structures. Letter A indicates the first protein complex of the light-dependent reactions, which is located in the thylakoid membrane. Letter B indicates the multiprotein complex between two photosystems. Letter C marks the second integral membrane protein complex of the light-dependent reactions. Letter D marks the substance inside thylakoid. Letter E indicates the flask-shaped structure, which has a canal for hydrogen ions. A B E D C
A
Chlorophyll can be found in _____. The figure shows the membrane of the thylakoid. Letters from A to E indicate definite structures. Letter A indicates the first protein complex of the light-dependent reactions, which is located in the thylakoid membrane. Letter B indicates the multiprotein complex between two photosystems. Letter C marks the second integral membrane protein complex of the light-dependent reactions. Letter D marks the substance inside thylakoid. Letter E indicates the flask-shaped structure, which has a canal for hydrogen ions. A and B B and E B and C A and C B and D
A and C
Chloroplast membrane vesicles are equilibrated in a simple solution of pH 5 . The solution is then adjusted to pH 8 . Which of the following conclusions can be drawn from these experimental conditions? The change in the solution's pH results in a gradient across the chloroplast membranes such that there is a lower concentration of protons inside the vesicles and a higher concentration outside. ATP will not be produced because there is no ADP and inorganic phosphate in the solution. Protons will not diffuse toward the outside of the vesicles. ATP will be produced because the proton gradient favors proton movement through the ATP synthase channels.
ATP will not be produced because there is no ADP and inorganic phosphate in the solution.
why?
All organisms use the sugars produced by photosynthesis to generate energy.
Energized electrons from ____ enter an electron transport chain and are then used to reduce NADP+. The figure shows the membrane of the thylakoid. Letters from A to E indicate definite structures. Letter A indicates the first protein complex of the light-dependent reactions, which is located in the thylakoid membrane. Letter B indicates the multiprotein complex between two photosystems. Letter C marks the second integral membrane protein complex of the light-dependent reactions. Letter D marks the substance inside thylakoid. Letter E indicates the flask-shaped structure, which has a canal for hydrogen ions. C E B D A
C
_____ releases energy that is used to pump hydrogen ions from the stroma into the thylakoid compartment. The figure shows the membrane of the thylakoid. Letters from A to E indicate definite structures. Letter A indicates the first protein complex of the light-dependent reactions, which is located in the thylakoid membrane. Letter B indicates the multiprotein complex between two photosystems. Letter C marks the second integral membrane protein complex of the light-dependent reactions. Letter D marks the substance inside thylakoid. Letter E indicates the flask-shaped structure, which has a canal for hydrogen ions.
C E B D A
What is the basic role of CO2 in photosynthesis? CO2 is fixed or incorporated into organic molecules. CO2 is taken in by plants as a form of inverse respiration, in which carbon dioxide is "breathed in" and oxygen is "breathed out." CO2 is a source of electrons in the formation of organic molecules.
CO2 is fixed or incorporated into organic molecules
which of these phosphorylates ADP to make ATP? The figure shows the membrane of the thylakoid. Letters from A to E indicate definite structures. Letter A indicates the first protein complex of the light-dependent reactions, which is located in the thylakoid membrane. Letter B indicates the multiprotein complex between two photosystems. Letter C marks the second integral membrane protein complex of the light-dependent reactions. Letter D marks the substance inside thylakoid. Letter E indicates the flask-shaped structure, which has a canal for hydrogen ions. D B E A C
E
Photorespiration occurs when rubisco combines RuBP with NADPH. glyceraldehyde 3-phosphate. CO2. citrate. O2.
O2
_____ has a longer wavelength than _____. Violet ... blue Yellow ... red Blue ... green Red ... green Green ... yellow
Red....green
NADP superscript plus sign, ADP, and H2O react in light reactions in the presence of light to produce ATP, NADPH, and O2. ATP, NADPH, and CO2 are used in the Calvin Cycle to produce ADP, NADP superscript plus sign, and sugar made of CH2O monomers. Select the correct statement about the Calvin cycle. The Calvin cycle has three phases: carbon fixation, reduction, and regeneration of RuBP. The basic function of the Calvin cycle is the conversion of solar energy to chemical energy. The Calvin cycle takes place primarily in the dark.
The Calvin cycle has three phases: carbon fixation, reduction, and regeneration of RuBP.
Which of the following statements best describes the relationship between the light-dependent and light-independent reactions of photosynthesis? View Available Hint(s) The light-independent reactions release energy, and the light-dependent reactions require energy. The light-dependent reactions pass electrons through an electron transport chain to the light-independent reactions. The light-dependent reactions produce carbon dioxide, which is then used by the light-independent reactions. The light-dependent reactions produce ATP and NADPH, which are then used by the light-independent reactions.
The light-dependent reactions produce ATP and NADPH, which are then used by the light-independent reactions.
What is the importance of the light-independent reactions in terms of carbon flow in the biosphere? The light-independent reactions turn CO2, a gas, into usable carbon in the form of sugars. The light-independent reactions use CO2 to make ATP. The light-independent reactions turn sugar into ATP for energy. The light-independent reactions turn glucose, a sugar, into CO2 gas.
The light-independent reactions turn CO2, a gas, into usable carbon in the form of sugars.
Plants are photoautotrophs. What does this mean? View Available Hint(s) They are the primary consumers of the biosphere. They use light energy to drive the synthesis of organic molecules from inorganic materials. They generate oxygen. They are attracted to light. They synthesize their own food from inorganic materials.
They use light energy to drive the synthesis of organic molecules from inorganic materials.
how?
Using the ATP and NADPH made during the light reactions, carbon is reduced in the Calvin cycle, and sugar is made.
CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they fix CO2 into organic acids in the mesophyll cells, which do not rely on stomata. fix CO2 into organic acids in the bundle-sheath cells, which do not rely on stomata. obtain CO2 through their roots during the day. fix CO2 into organic acids during the night when temperatures are cooler. fix CO2 into by combining it with RuBP in the Calvin cycle.
fix CO2 into organic acids during the night when temperatures are cooler
How is photosynthesis similar in C4 plants and CAM plants? Both types of plants make most of their sugar in the dark. In both cases, rubisco is not used to fix carbon initially. Both types of plants make sugar without the Calvin cycle. In both cases, electron transport is not used.
in both cases, rubisco is not used to fix carbon initially.
Which process is most directly driven by light energy? removal of electrons from chlorophyll molecules reduction of NADP+ molecules creation of a pH gradient by pumping protons across the thylakoid membrane ATP synthesis
removal of electrons from chlorophyll molecules reduction of NADP+ molecules
C4 plants occur more commonly in desert conditions because __________. they produce water as a product of their photosynthetic pathways they store carbon by incorporating CO2 into organic acids that are later catabolized they produce carbon dioxide internally via photorespiration the stomata open at night and close in the day they can fix carbon at the lower CO2 concentrations that develop when the stomata are closed
they can fix carbon at the lower CO2 concentrations that develop when the stomata are closed
What is the biological significance of the light-independent reactions of photosynthesis? View Available Hint(s) They convert ATP to sugar. They make oxygen. They generate ATP and NADPH. They convert carbon dioxide to sugar.
they convert carbon dioxide to sugar