Chapter 10

The molecules that absorb only certain wavelengths of light energy from the Sun in order to begin the photosynthetic reactions are called _____. -chloroplasts -oxygen -pigments -stroma

During photosynthesis, the light energy from the Sun is captured and stored in the bonds of _____. -oxygen -hemoglobin -water -glucose

Why does a leaf appear green when a person looks at it? -The chlorophyll pigments absorb all wavelengths of light except in the green spectrum, which it reflects. -The chlorophyll pigments reflect all wavelengths of light except in the green spectrum, which it absorbs. -Only the green wavelengths of light from the Sun reach the Earth. -The chlorophyll pigments are colored green.

When a photon of light is absorbed by a pigment molecule, electrons in the molecule _____. -enter an excited state -remain unchanged -are blown away from the entire complex -fall back down to ground level

Both photosystem I and photosystem II employ the use of a(n) _____, which drives the formation of ATP and NADPH. -electron transport chain -ferredoxin shuttling chain -calvin cycle -citric acid cycle

What important molecule that is needed for cellular respiration is released when water is split in the light reactions of photosynthesis? -rubisco -oxygen -chlorophyll -carbon dioxide

During the Calvin cycle, carbon dioxide is _____, in order to drive the formation of sugars. -destroyed -produced -oxidized -reduced

Plant leaves contain openings called _____, which allow the diffusion of carbon dioxide into the leaf tissue. -stomata -mesophyll -calvins -CAM

The most abundant enzyme on Earth, which catalyzes the fixation of carbon dioxide in photosynthesis, is _____. -carbon dioxidase -carotenoids -chlorophyll -rubisco

Why is photosynthesis so important to life on Earth? -Photosynthesis is used to drive the formation of carbon dioxide, which releases the energy that allows the planet Earth to remain warm. -Photosynthesis breaks down glucose, which provides ATP for all plants and animals. -Photosynthesis releases carbon dioxide into the air, which is then used during cellular respiration, which in turn drives the release of oxygen, completing the respiration cycle. -Photosynthesis captures light energy from the Sun and stores it in the bonds of glucose, which is then used during cellular respiration to drive the formation of ATP in all plants and animals.

When is light energy transformed into chemical energy? -Between the antenna complex and photosystem II -Between photosystem II and chemiosmosis -Between the Calvin cycle and glucose -Between chemiosmosis and ATP

Where do the excited electrons flowing through photosystem I originally come from? -O2 -Antenna complex -H2O -Sunlight

A newly identified plant virus infects and kills its host by inserting large protein channels into thylakoid membranes, creating permanent holes. Which arrow would you cross out to represent the effect of these holes? -Between the Calvin cycle and glucose -Between the antenna complex and photosystem II -Between photosystem II and chemiosmosis -Between photosystem I and NADPH

Under what conditions will cells use fermentation pathways? -When available acetyl CoA is low. -When production of NADH is low. -When an ETC electron acceptor is not available. -When glucose is not available.

A newly developed insecticide compound steals high-energy electrons from FADH2 and NADH before they can bind to the electron transport chain. Why does this kill insects? -Glycolysis reactions are blocked. -Fermentation pathways will be switched on, supplying insufficient ATP to maintain the insect. -The ETC cannot establish a proton gradient to drive chemiosmotic production of ATP. -Citric acid cycle oxidation of glucose cannot proceed.

You are interested in identifying mutant yeast cells that have impaired or broken ETC proteins. What phenotype would you look for to find those mutant cells? -Look for cells that cannot grow without oxygen. -Look for cells that do not release CO2. -Look for cells that grow at similar rates with or without oxygen. -Look for cells that cannot recycle NADH.

Which processes establish a gradient of protons to drive ATP synthesis? -Mitochondrial electron transport chain and photosystem I reactions -Glycolysis and photosystem I reactions -Photosystem II and mitochondrial electron transport chain reactions -Photosystem II and Calvin cycle reactions

Which of the following BEST characterizes gas exchange in animal versus plant metabolism: -Animals take in and release both O2 and CO2. Plants take in CO2 and release O2. -Animals take in O2 and release CO2. Plants take in and release both O2 and CO2. -Both animals and plants take in and release O2 and CO2. -Animals take in O2 and release CO2. Plants take in CO2 and release O2.

Which statement accurately describes the roles of the light-dependent reactions (LDRs), the Calvin cycle, and cellular respiration? -The LDRs convert small high-energy molecules into sugars, the Calvin cycle breaks down sugars to produce ATP, and cellular respiration converts light energy into chemical energy. -The LDRs convert light energy into chemical energy, the Calvin cycle breaks down sugars to produce ATP, and cellular respiration converts small high-energy molecules into sugars. -The LDRs convert small high-energy molecules into sugars, the Calvin cycle converts light energy into chemical energy, and cellular respiration breaks down sugars to produce ATP. -The LDRs convert light energy into chemical energy, the Calvin cycle converts small high-energy molecules into sugars, and cellular respiration breaks down sugars to produce ATP.

Consistently overwatering a potted tomato plant will eventually kill it. Using the map, suggest why waterlogged soil results in plant death. -CO2 cannot reach the chloroplasts, preventing production of glucose by the Calvin cycle. The plant cannot make food and starves. -O2 cannot reach respiring root cells. The plant cannot oxidize food and starves. -Light energy cannot reach the chloroplasts, preventing ATP and NADPH production by the light-dependent reactions. The plant cannot make food and starves. -CO2 cannot reach photosynthesizing root cells, preventing production of glucose by the Calvin cycle. The plant cannot make food and starves.

_____ has a longer wavelength than _____. -Red ... green -Yellow ... red -Violet ... blue -Green ... yellow -Blue ... green

Which of these equations best summarizes photosynthesis? -C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy -C6H12O6 + 6 O2 → 6 CO2 + 12 H2O -6 CO2 + 6 H2O → C6H12O6 + 6 O2 -H2O → 2 H+ + 1/2 O2 + 2e- -6 CO2 + 6 O2 → C6H12O6 + 6 H2O

The light reactions of photosynthesis use _____ and produce _____. carbon dioxide ... oxygen -NADPH ... oxygen -NADPH ... NADP+ -water ... NADPH -carbon dioxide ... sugar

Which process produces oxygen? -Cellular respiration -Photosynthesis

Which set of reactions uses H2O and produces O2? -The light-dependent reactions -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 sugar into ATP for energy. -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 glucose, a sugar, into CO2 gas.

True or false? The light-dependent reactions of photosynthesis use water and produce oxygen.

Which of the following molecules is the primary product of photosystem I? -Carbon dioxide -NADPH -ATP -Oxygen

What is the biological significance of the light-independent reactions of photosynthesis? -They convert ATP to sugar. -They make oxygen. -They generate ATP and NADPH. -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 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-independent reactions release energy, and the light-dependent reactions require energy. -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? -Production of 3-phosphoglycerate -Production of G3P -Regeneration of RuBP -Carbon fixation

Which term describes ATP production resulting from the capture of light energy by chlorophyll? -Substrate-level phosphorylation -Dephosphorylation -Oxidative phosphorylation -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.

According to the chemiosmotic hypothesis, what provides the energy that directly drives ATP synthesis? -Temperature gradient -Proton gradient -Electrons -Osmotic gradient

Which of the following particles can pass through the ATP synthase channel? -ATP -ADP -Protons -Inorganic phosphate

True or false? The region of ATP synthase that catalyzes the production of ATP from ADP and inorganic phosphate spans the chloroplast membrane.

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. -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. -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.