Campbell Chapter 10: Mastering Biology Questions
Which of these equations best summarizes photosynthesis?6 CO2 + 6 H2O > C6H12O6 + 6 O2
Where does the Calvin cycle occur?Stroma
The light reactions of photosynthesis use _____ and produce _____.water … NADPH
The photosynthetic membranes are found in the _____ in plant cells.chloroplasts
Which term describes ATP production resulting from the capture of light energy by chlorophyll?Photophosphorylation
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.False
According to the chemiosmotic hypothesis, what provides the energy that directly drives ATP synthesis?Proton gradient
Which of the following particles can pass through the ATP synthase channel?Protons
True or false? The region of ATP synthase that catalyzes the production of ATP from ADP and inorganic phosphate spans the chloroplast membrane.False
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?ATP will not be produced because there is no ADP and inorganic phosphate in the solution.
_____ has a longer wavelength than _____.Red … green
Which of the following is a product of the light reactions of photosynthesis?oxygen, ATP, and NADPH
Photosynthesis is a redox reaction. This means that H2O is _____ during the light reactions and CO2 is _____ during the Calvin cycle.oxidized…reduced
In the electromagnetic spectrum, the type of radiation that we call visible light occurs between _____.ultraviolet radiation and infrared radiation
Approximately what wavelength of light is best absorbed by chlorophyll a, the pigment that participates directly in the light reactions?435 nm
Which wavelength of light is best absorbed by chlorophyll b?455 nm
You obtain the pigments called carotenoids in your diet when you eat carrots. Why do carotenoids appear yellow and orange?They absorb blue/green light and reflect yellow and red wavelengths of light.
Can you tell from these absorption spectra whether red light is effective in driving photosynthesis?One cannot tell from this graph, but because chlorophyll a does absorb red light, we can predict that it would be effective in driving photosynthesis.
If only chlorophyll a were involved in the light reactions, would blue light (wavelength about 490 nm) be effective in driving photosynthesis?The graph indicates that chlorophyll a absorbs very little blue light, so we can predict that blue light would not be effective.
An action spectrum plots the rate of photosynthesis at various wavelengths of visible light, and it shows that blue light with a wavelength of about 490 nm is effective in driving photosynthesis. Based on this information and the absorption spectra shown at left, what role may chlorophyll b and carotenoids play in photosynthesis?These pigments are able to absorb more wavelengths of light (and thus more energy) than chlorophyll a alone can absorb. As part of light-harvesting complexes in photosystems, they broaden the range of light that can be used in the light reactions.
The overall function of the Calvin cycle is _____.making sugar
Carbon fixation involves the addition of carbon dioxide to _____.RuBP
After 3-PGA is phosphorylated, it is reduced by _____.NADPH
How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose?6
In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?3
Which process produces oxygen?Photosynthesis
Which set of reactions uses H2O and produces O2?The light-dependent 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.
True or false? The light-dependent reactions of photosynthesis use water and produce oxygen.True
Which of the following molecules is the primary product of photosystem I?NADPH
What is the biological significance of the light-independent reactions of photosynthesis?They convert carbon dioxide to sugar.
Which of the following statements best describes the relationship between the light-dependent and light-independent reactions of photosynthesis?The light-dependent reactions produce ATP and NADPH, which are then used by the light-independent reactions.
Which of the following reactions ensures that the Calvin cycle can make a continuous supply of glucose?Regneration of RuBP
Which of the following products of the light reactions of photosynthesis is consumed during the Calvin cycle?NADPH
C4 plants occur more commonly in desert conditions because _____.they can fix carbon at the lower CO2 concentrations that develop when the stomata are closed
In C3 plants the conservation of water promotes _____.photorespiration
In C4 and CAM plants carbon dioxide is fixed in the _____ of mesophyll cells.cytoplasm
C4 plants differ from C3 and CAM plants in that C4 plants _____.transfer fixed carbon dioxide to cells in which the Calvin cycle occurs
Plants are photoautotrophs. What does this mean?They use light energy to drive the synthesis of organic molecules from inorganic materials.
Which of the following does not occur during the Calvin cycle?release of oxygen
Which process is most directly driven by light energy?removal of electrons from chlorophyll molecules
The ultimate source of energy to support most life on Earth is _____.sunlight
The light reactions of photosynthesis supply the Calvin cycle withATP and NADPH.
Which of the following statements is a correct distinction between autotrophs and heterotrophs?Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic.
In any ecosystem, terrestrial or aquatic, what group(s) is (are) always necessary?autotrophs
When oxygen is released as a result of photosynthesis, it is a direct by-product ofsplitting water molecules.
Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle?ATP and NADPH
Where does the Calvin cycle take place?stroma of the chloroplast
The splitting of carbon dioxide to form oxygen gas and carbon compounds occurs duringneither photosynthesis nor respiration
Which statement describes the functioning of photosystem II?The electron vacancies in P680+ are filled by electrons derived from water.
In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons fromthe stroma to the thylakoid space.
Generation of proton gradients across membranes occurs duringboth photosynthesis and respiration.
Photorespiration occurs when rubisco reacts RuBP withO2.
Compared to C3 plants, C4 plantscan continue to fix CO2 even at relatively low CO2 concentrations and high oxygen concentrations.
CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because theyfix CO2 into organic acids during the night.
Увы, теперь, несмотря на силу рук, он не мог подтянуться, чтобы влезть обратно. Плечи его отчаянно болели, а грубый камень не обеспечивал достаточного захвата и впивался в кончики пальцев подобно битому стеклу.
Беккер понимал, что через несколько секунд его преследователь побежит назад и с верхних ступеней сразу же увидит вцепившиеся в карниз пальцы. Он зажмурился и начал подтягиваться, понимая, что только чудо спасет его от гибели.