Bio 7 – Flashcards

In an _____ process, photosynthesis _____ carbon, whereas cellular respiration is an _____ process that _____ carbon. endergonic ... oxidizes ... exergonic ... reduces exergonic ... reduces ... endergonic ... oxidizes endergonic ... reduces ... exergonic ... oxidizes endergonic ... oxidizes ... endergonic ... reduces

Which of the following are produced during the light reactions of photosynthesis? 18) A) glucose, ADP, NADP+, CO2 B) ADP, NADP+, O2 C) ATP, NADPH, O2 D) ATP, NADPH, CO2 E) glucose, ADP, NADP+

Where do the electrons needed by photosystem II originate? water ATP other chlorophyll molecules the electron transport chain

Which of the following colors is most strongly reflected by chlorophyll? yellow orange green red

Chlorophyll is found in the _____ of chloroplasts. thylakoid membranes stroma outer membrane thylakoid space

Photophosphorylation during photosynthesis differs from oxidative phosphorylation during cellular respiration in that it involves an electron transport chain. energy is stored in the form of a proton (H+) concentration difference. generation of ATP is driven by a flow of protons (H+) through ATP synthase. the final electron acceptor is NADP+ and not oxygen.

Photosystem II 26) A) is reduced by NADPH. B) does not have a reaction center. C) releases CO2 as a by-product. D) has P700 at its reaction center. E) passes electrons to photosystem I.

The photosynthetic event known as the Calvin cycle occurs in the _____. stroma stomata thylakoid compartment thylakoid membrane

Which of the following is the correct flow of electrons through the two photosystems in the thylakoid membrane? P680→ P700 → NAD+ P700 → NADP+ → ATP → P680 P700 → NADP+ → P680 P680 → P700 → NADP+

You could distinguish a granum from an inner mitochondrial membrane because the granum, but not the inner mitochondrial membrane, would _____. be inside a mitochondrion function in energy transformation have photosynthetic pigments contain protein but not lipids

Where is chlorophyll found in a plant cell? cytoplasm thylakoid membranes stroma cristae

CO2 enters and O2 escapes from a leaf via stroma. grana. stomata. thylakoids.

As a result of the cascade of electrons down the electron transport chains of the light reactions, NADP+ is oxidized to NADPH. NADPH is oxidized to NADP+. NADP+ is reduced to NADPH. NADPH is reduced to NADP+.

NADP+ is required for photosynthesis because it _____. forms NADPH to be used in the Calvin cycle forms part of photosystem II helps produce ATP from the light reactions absorbs light energy

The electron transport chains of the light reactions shuttle electrons along in a series of redox reactions. provide energy for the citric acid cycle. are found on the plasma membrane of mesophyll cells. are located in the stroma.

What is the main adaptive advantage of the C4 and CAM photosynthesis strategies over the C3 strategy? They make it possible for the plant to use the Calvin cycle at night. They allow the plant to fix carbon more efficiently under conditions of low atmospheric CO2. They help the plant conserve water and synthesize glucose efficiently under hot, dry conditions. They allow the plant to fix carbon more efficiently in dim or cool conditions.

The Calvin cycle constructs ________, an energy-rich molecule that a plant cell can then use to make glucose or other organic molecules. carbon dioxide G3P NADH ATP

The light reactions of photosynthesis generate high-energy electrons, which end up in _____. The light reactions also produce _____ and _____. ATP ... NADPH ... oxygen NADPH ... ATP ... oxygen chlorophyll ... ATP ... NADPH oxygen ... sugar ... ATP

In photophosphorylation, energy from electron flow is used to transport ________ from the ________ to the thylakoid compartment, generating a concentration gradient of ________. H+ . . . grana . . . electrons H+ . . . stroma . . . H+ electrons . . . grana . . . H+ H+ . . . stroma . . . ATP

What is the name given to organisms that can make their own food and thus sustain themselves without consuming organic molecules derived from other organisms? heterotrophs synthesizers chemotrophs autotrophs

The electrons lost from the reaction center of photosystem II are replaced by electrons from ATP. H2O. CO2. photosystem I.

During photosynthesis, an electron transport chain is used to _____. transport NADPH from the light reactions to the Calvin cycle transport excited electrons from P680 to an electron acceptor transport excited electrons from P700 to an electron acceptor transport electrons from photosystem II to photosystem I

The full range of electromagnetic energy is called the ________ spectrum. energy ultraviolet visible electromagnetic

The impact of a sufficiently large asteroid or comet is one of the theories that have been put forward to explain why dinosaurs became extinct. Why would this extinction-level event have such a major impact? It created enormous tidal waves and huge forest fires. The toxic fumes produced meant that the dinosaurs could no longer breathe. It increased the temperature of the planet. It produced dust and other particulates that would block out the sun.

Photorespiration is an inefficient process that occurs when plants close their stomata to avoid dehydration in arid climates. C4 and CAM plants have adapted to this situation because _____. they produce water as a product of their photosynthetic pathways. This allows them to replace the water lost by dehydration their stomata open at night and close in the day. Thus, water is no longer lost due to evaporation they produce CO2 internally. Thus, they avoid opening their stomata to gain atmospheric CO2 they fix CO2 into a four-carbon compound. This creates a steeper concentration gradient within the mesophyll cells

The energy that excites the photosystems is supplied by photons. electrons passing down the electron transport chain. NADPH. ATP.

What is the source of energy that provides the boost for electrons during photosynthesis? ATP cellular respiration light electromagnetism

Carbon dioxide enters a leaf through the _____. thylakoids mesophyll stomata chloroplasts

The source of the oxygen produced by photosynthesis has been identified through experiments using radioactive tracers. Follow the equation below and determine where oxygen comes from. water light carbon dioxide glucose

When chloroplast pigments absorb light, _____. they become reduced their electrons become excited the Calvin cycle is triggered they lose potential energy

The process of photosynthesis arose roughly two billion years ago. Its origin had a huge impact on existing organisms and on the physical characteristics of the biosphere. Which major physical change could be attributed to photosynthesis? Photosynthesis drastically increased the oxygen content of the atmosphere. Photosynthesis drastically increased the carbon dioxide content of the atmosphere. Photosynthesis drastically raised Earth's surface temperature. Photosynthesis allowed much higher levels of ultraviolet light to reach Earth's surface.

What is the role of NADP+ in photosynthesis? It is part of the electron transport chain and is involved with the manufacture of ATP. It acts as the primary electron acceptor for the photosystems. It is reduced and then carries electrons to the Calvin cycle. It assists chlorophyll in capturing light.

Which of the following statements comparing photosynthesis and cellular respiration is false? Photosynthesis produces O2; respiration produces CO2. Photosynthesis is ultimately powered by light energy and respiration by the chemical energy of fuel molecules. Photosynthesis consumes CO2; respiration consumes O2. ATP is not produced during photosynthesis; it is produced only during cellular respiration.

CAM plants have adapted to arid environments by closing their stomata during the day. However, photosynthesis still occurs. This is because _____ some CO2 leaks through the closed stomata CO2 is fixed in the bundle-sheath cells photosynthesis occurs at night

Rubisco is the _____. enzyme responsible for splitting H2O to produce O2 in photosynthesis first stable intermediate in CAM metabolism enzyme in C3 plants that first captures CO2 to begin the Calvin cycle enzyme that forms a four-carbon compound in CAM metabolism

Autotrophs that utilize light as their energy source are photoautotrophs. chemosynthetic autotrophs. fungi. heterotrophs.

In addition to its function in mitochondria, the chemiosmotic mechanism is important for generating ATP during the _____. photoexcitation of electrons synaptic transmission process of intracellular digestion within lysosomes fermentation of glucose

Plant cells have mitochondria and chloroplasts. lack mitochondria and chloroplasts. have mitochondria but do not have chloroplasts. lack mitochondria but have chloroplasts.

Photosynthetic organisms derive their carbon from carbon monoxide. hydrocarbons. methane. carbon dioxide.

Which statement regarding the light reactions is true? Photoexcited electrons pass from photosystem I to photosystem II. ATP synthesis occurs as electrons "fall" down the electron transport chain. Electrons are supplied to chlorophyll P680 as it reduces the primary electron acceptor. Glucose is a product of the light reactions.

Put the following steps of the Calvin cycle in the correct order: 1. Carbon fixation 2. Regeneration of RuBP 3. Release of G3P 4. Reduction

Put the following steps of the light reactions in the correct order: 1. Light excites an electron from photosystem I. 2. Light excites an electron from photosystem II. 3. Electrons reduce NADP+ to NADPH. 4. Electrons pass through an electron transport chain, which generates a H+ gradient used to make ATP.