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Where does the Calvin cycle take place?

stroma of the chloroplast

In autotrophic bacteria, where are the enzymes located that can carry on organic synthesis?

along the inner surface of the plasma membrane

When oxygen is released as a result of photosynthesis, it is a by-product of what process?

splitting the water molecules

What group(s) is (are) always necessary in any ecosystem?

autotrophs

What did Engelmann conclude about the congregation of bacteria in the red and blue areas?

Bacteria congregated in these areas because these areas had the most oxygen being released.

What was an outcome of Engelmann's experiment?

to help determine the relationship between wavelengths of light and the oxygen released during photosynthesis

If light is not filtered through a prism in Engelmann's experiment, what would happen?

The bacteria would be relatively evenly distributed along the algal filaments.

Why do the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis differ?

Other pigments absorb light in addition to chlorophyll a.

What wavelength of light is most effective in driving photosynthesis?

420 nm

How does photosystem I function?

The excitation is passed along to a molecule of P680 chlorophyll in the photosynthetic unit.

How can one detect the lack of photosystem II in some photosynthetic organisms?

by testing for liberation of O₂ in the light.

What are the products of linear photophosphorylation?

ATP and NADPH

What will happen if a thylakoid is punctured?

It will most directly affect the synthesis of ATP.

What does the chemiosmotic process in chloroplasts involve?

establishment of a proton gradient

What happens if isolated chloroplasts are made acidic and then transferred to a pH-8 solution?

The isolated chloroplasts will make ATP.

Where are the ATP synthase complexes located in a plant cell?

thylakoid membrane

In chloroplasts, where are protons translocated from?

the stroma to the thylakoid space

What is the relationship between photosynthesis and respiration?

Photosynthesis stores energy in complex organic molecules, while respiration releases it.

When does synthesis of ATP by the chemiosmotic mechanism occur?

during both photosynthesis and respiration

When does reduction of oxygen to form water occur?

during respiration

When does the splitting of carbon dioxide to form oxygen gas occur?

during photosynthesis

When does generation of proton gradients across membranes occur?

during both photosynthesis and respiration

What does the presence of PS I and absence of PS II imply?

psi was first

What function do carotenoids have in plants?

They dissipate excessive light energy.

What is the relationship between the light reactions and the Calvin cycle?

The light reactions provide ATP and NADPH to the Calvin cycle.

Where do the enzymatic reactions of the Calvin cycle take place?

stroma of the chloroplast

What is the primary function of the Calvin cycle?

synthesize simple sugars from carbon dioxide

Which process produces molecular oxygen (O₂)?

light reactions alone

Which process requires ATP?

the Calvin cycle alone

Which process produces NADH?

neither the light reactions nor the Calvin cycle

Which process produces NADPH?

light reactions alone

Which process produces three-carbon sugars?

the Calvin cycle alone

Which process requires CO₂?

the Calvin cycle alone

Which process requires glucose?

neither the light reactions nor the Calvin cycle

What is the expected relationship between the pH of the inner thylakoid space and the stroma?

The pH within the thylakoid is less than that of the stroma.

What does Figure 10.3 represent?

cell processes involved in C₄ photosynthesis.

In which cell would oxygen inhibit the CO₂ fixation reactions?

cell II only

What type of plant incorporates radioactive carbon (¹⁴C) first into oxaloacetate?

C₄ plant

Why can C₄ plants photosynthesize with no apparent photorespiration?

They use PEP carboxylase to initially fix CO₂.

How do CAM plants reduce water loss?

They fix CO₂ into organic acids during the night.

What are metabolic pathways that release stored energy by breaking down complex molecules called?

catabolic pathways

What happens in the reaction C₆H₁₂O₆ + 6O₂ → 6CO₂ + H₂O + Energy?

C₆H₁₂O₆ is oxidized and O₂ is reduced.

Where does glycolysis take place?

cytosol

How is ATP generated during glycolysis?

substrate-level phosphorylation

What is the role of oxygen in cellular respiration?

to accept electrons at the end of the electron transport chain

What happens to a molecule that is phosphorylated?

It has increased chemical reactivity; it is primed to do cellular work.

Where does acetyl-CoA accumulate during cellular respiration?

mitochondrial matrix

When is carbon dioxide (CO₂) released during cellular respiration?

during oxidation of pyruvate to acetyl-CoA and the citric acid cycle

Where is the most chemical energy harvested during cellular respiration?

from chemiosmotic phosphorylation

In aerobic respiration, in what sequence do electrons travel?

food → NADH → electron transport chain → oxygen

Where are the proteins of the electron transport chain located?

mitochondrial inner membrane

What is the primary role of oxygen in cellular respiration?

to act as an acceptor for electrons and hydrogen, forming water

What is the most direct source of energy used to convert ADP + Pi to ATP in chemiosmotic phosphorylation?

energy released from movement of protons through ATP synthase

What is proton-motive force?

the transmembrane proton concentration gradient

What is the purpose of the large inner mitochondrial membrane surface area?

it increases the surface for oxidative phosphorylation

What substances are initially added to the electron transport chain?

NADH, FADH₂, and electrons

What couples chemiosmosis to energy storage?

ATP synthase

What process normally occurs whether or not oxygen is present?

glycolysis

What is one function of both alcohol fermentation and lactic acid fermentation?

to oxidize NADH to NAD⁺

Why is glycolysis considered one of the first metabolic pathways to have evolved?

It does not involve oxygen and is present in nearly all organisms.

Where do the catabolic products of fatty acid breakdown enter the citric acid cycle?

acetyl-CoA