Life is solar powered. Almost all the producers of the biosphere depend on energy from

The light reactions of photosynthesis supply the Calvin cycle with a. light energy. b. CO2 and ATP. c. H2O and NADPH. d. ATP and NADPH. e. sugar and O2.

Which of the following sequences correctly represents the flow of electrons during photosynthesis? a. NADPH O2 CO2 b. H2O NADPH Calvin cycle c. NADPH chlorophyll Calvin cycle d. H2O photosystem I photosystem II e. NADPH electron transport chain O2

How is photosynthesis similar in C4 plants and CAM plants? a. In both cases, electron transport is not used. b. Both types of plants make sugar without the Calvin cycle. c. In both cases, rubisco is not used to fix carbon initially. d. Both types of plants make most of their sugar in the dark. e. In both cases, thylakoids are not involved in photosynthesis.

Which of the following statements is a correct distinction between autotrophs and heterotrophs? a. Only heterotrophs require chemical compounds from the environment. b. Cellular respiration is unique to heterotrophs. c. Only heterotrophs have mitochondria. d. Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic. e. Only heterotrophs require oxygen.

Which of the following does not occur during the Calvin cycle? a. carbon fixation b. oxidation of NADPH c. release of oxygen d. regeneration of the CO2 acceptor e. consumption of ATP

In mechanism, photophosphorylation is most similar to a. substrate-level phosphorylation in glycolysis. b. oxidative phosphorylation in cellular respiration. c. the Calvin cycle. d. carbon fixation. e. reduction of NADP

Which process is most directly driven by light energy? a. creation of a pH gradient by pumping protons across the thylakoid membrane b. carbon fixation in the stroma c. reduction of NADP+ molecules d. removal of electrons from chlorophyll molecules e. ATP synthesis

To synthesize one glucose molecule, the Calvin cycle uses _______ molecules of CO2, _______ molecules of ATP, and _______ molecules of NADPH.

The following diagram represents an experiment with isolated thylakoids. The thylakoids were first made acidic by soaking them in a solution at pH 4. After the thylakoid space reached pH 4, the thylakoids were transferred to a basic solution at pH 8. The thylakoids then made ATP in the dark. (See Concept 2.5 to review pH.) pH 7 pH 4 pH 4 pH 8 ATP Draw an enlargement of part of the thylakoid membrane in the beaker with the solution at pH 8. Draw ATP synthase. Label the areas of high H+ concentration and low H+ concentration. Show the direction protons flow through the enzyme, and show the reaction where ATP is synthesized. Would ATP end up in the thylakoid or outside of it? Explain why the thylakoids in the experiment were able to make ATP in the dark.

Scientific evidence indicates that the CO2 added to the air by the burning of wood and fossil fuels is contributing to global warming, a rise in global temperature. Tropical rain forests are estimated to be responsible for approximately 20% of global photosynthesis, yet the consumption of large amounts of CO2 by living trees is thought to make little or no net contribution to reduction of global warming. Why might this be? (Hint: What processes in both living and dead trees produce CO2?)

Consider the endosymbiont theory (see Concept 4.5) and the fact that chloroplasts contain DNA molecules. Given that chloroplast DNA has genes, what would you expect if you compared the sequence of a chloroplast gene in a plant cell to the same gene in other plant species or bacteria? Would it be more similar to a plant or a bacterial gene sequence?

Life is solar powered. Almost all the producers of the biosphere depend on energy from the sun to produce the organic molecules that supply the energy and carbon skeletons needed for life. In a short essay (100150 words), describe how the process of photosynthesis in the chloroplasts of plants transforms the energy of sunlight into the chemical energy of sugar molecules.