Chapter 10 - Photosynthesis

How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose?

6 - Six carbon dioxide molecules are required to produce two G3P molecules, which can be combined to make one glucose molecule.

What is the equation for photosynthesis?

6CO2 + 6H2O ------> C6H12O6 + 6O2

Which of the following products of the light reactions of photosynthesis is consumed during the Calvin cycle? A) NADPH B) sugar C) ADP + Pi D) oxygen E) water

A) NADPH

What phosphorylates ADP to make ATP?

ATP synthase

How are the light reactions in photosynthesis related to oxidative phosphorylation in cellular respiration?

Chloroplasts form ATP and NADPH in a manner similar to the formation of ATP and NADH in mitochondria-Pass high-energy electrons to a lower energy acceptor

What are the products of the light reactions of photosynthesis?

CO2, Oxygen, NADPH

What are the three phases of the Calvin Cycle?

Carbon fixation, reduction, and regeneration of the CO2 acceptor (RuBP)

What process is directly associated with photosystem I?

Receiving electrons from the thylakoid membrane electron transport chain

Carbon fixation involves the addition of carbon dioxide to _____.

RuPB

The oxygen released by photosynthesis is produced by what process?

Splitting water molecules

When light strikes chlorophyll molecules, they lose electrons, which are ultimately replaced by _____.

Splitting water. The electrons removed from water are transferred to p680.

For net synthesis of 1 G3P, the cycle must take place how many times?

Three time, fixing three molecules of CO2

Where are ATP synthase complexes located in plant cells?

Thylakoid membrane and inner mitochondrial membrane

True or false: Photosynthesis is an endergonic process.

True

In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?

3

What is photophosphorylation?

Adding phosphate to a molecule using light

What event accompanies absorption of energy by chlorophyll molecules of the reaction-center complex?

An electron is excited.

Which terms describe two atoms when they form a bond in which electrons are completely transferred from one atom to the other?

Anion and cation

Which of the following statements is not true of most cellular redox reactions? A) Changes in potential energy can be released as heat. B) A hydrogen atom is transferred to the atom that loses an electron. C) The reactant that is oxidized loses electrons. D) The electron acceptor is reduced.

B) A hydrogen atom is transferred to the atom that loses an electron.

Which of the following processes is most directly driven by light energy? A) creation of a pH gradient by pumping protons across the thylakoid membrane B) removal of electrons from chlorophyll molecules C) carbon fixation in the stroma D) reduction of NADP+ molecules

B) removal of electrons from chlorophyll molecules

Which of the following processes would be most directly affected if a thylakoid membrane is punctured so that the interior of the thylakoid is no longer separated from the stroma? A) flow of electrons from photosystem II to photosystem I B) synthesis of ATP C) splitting of water D) reduction of NADP+

B) synthesis of ATP

When donating its activated electron, the chlorophyll in photosystem II (P680) becomes P680+ and a very powerful oxidizing agent. This is best shown by its ability to: A. make use of a proton electrochemical gradient to drive the formation of ATP. B. force the oxidation of oxygen in water to oxygen gas. C. donate an electron to plastoquinone (Pq). D. absorb light energy to power redox reactions. E. force the reduction of NADP+ to NADPH.

B. force the oxidation of oxygen in water to oxygen gas.

One good reason for carrying out the production of oxygen gas (O2) in the thylakoid space, and not in the stroma of the chloroplasts, is... A. that this makes it easier for O2 to exit the chloroplast. B. that the hydrogen ions released can contribute to the H+ electrochemical gradient being generated. C. to reduce the concentration of O2 in the stroma so that organic matter located there is not oxidized by it. D. that the concentration of water in this space is high, making it easier to form O2 from the water. E. that carrying out this process in the stroma would tend to dry out this compartment and denature the enzymes of the Calvin cycle located there.

B. that the hydrogen ions released can contribute to the H+ electrochemical gradient being generated.

Which of the following statements is true of the bonds in a water molecule? A) Oxygen acts as the electron acceptor and is oxidized. B) The electron in each hydrogen atom is completely transferred to the oxygen atom, and each hydrogen atom has a net charge of +1. C) Oxygen holds electrons more tightly than hydrogen does, and the net charge is zero. D) There is equal sharing of the electrons between the oxygen atom and the two hydrogen atoms, and the net charge is zero.

C) Oxygen holds more tightly that hydrogen does, and the net charge is zero.

A small acorn over time can grow into a huge oak tree. The wood in such a tree can weigh many tons, even after it has been cut into logs and dried. Where does most of this mass come from as the tree grows? A.Minerals in the soil B.Organic matter in the soil C.Gases in the air D.SunlightE.ATP

C. Gases in the air

To slow down global warming, scientists believe it is crucial to stop cutting down the Amazon rain forest, mainly because: A.Many plant and animal species will disappear if the rain forest ecosystem is destroyed. B.Removal of the forest will lead to wide-spread erosion and degradation of the environment. C.Living trees remove carbon dioxide (CO2) from the atmosphere. D.The decay of cut trees will release CO2 into the atmosphere.

C. Living trees remove carbon dioxide (CO2) from the atmosphere

Which of the following molecules are products of the light reactions of photosynthesis that are utilized in the Calvin cycle? A) H2O and O2 B) ADP, Pi, and NADP+ C) CO2 and glucose D) ATP and NADPH

D) ATP and NADPH

Which of the following INCORRECTLY matches a process with its typical location? A) Oxygen gas is produced—the soluble space surrounded by the thylakoid membranes B) Activated chlorophyll donates an electron—in the thylakoid membranes C) NADPH is oxidized to NADP—the stroma of the chloroplast D) ATP is produced—the space between the chloroplast outer and inner membranes E) RUBISCO catalyzes carbon fixation—the stroma of the chloroplast

D) ATP is produced—the space between the chloroplast outer and inner membranes

Some photosynthetic organisms contain chloroplasts that lack photosystem II, yet are able to survive. What approach would be the best way to detect the lack of photosystem II in these organisms?

Determine whether they produce O2 in the light.

Which term describes the degree to which an element attracts electrons?

Electronegativity

_____ releases energy that is used to pump hydrogen ions from the stroma into the thylakoid compartment.

Electrons passed along the electron transport chain

What is the flow of electrons during photosynthesis?

H2O → NADPH → Calvin cycle

What molecule is the final electron acceptor for electrons from photosystem I?

NADP+

After 3-PGA is phosphorylated, it is reduced by _____.

NADPH

The reducing power for Calvin cycle reactions is provided by what molecule?

NADPH

Gaseous hydrogen burns in the presence of oxygen to form water: 2H2 + O2 → 2H2 O + energy Which molecule is oxidized and what kind of bond is formed?

Hydrogen, polar

What is carbon fixation?

It is the initial incorporation of CO2 into organic material. Catalyzed by RuPB

What happens to the free energy released as electrons are passed from photosystem II to photosystem I through a series of electron carriers?

It is used to establish and maintain a proton gradient.

The overall function of the Calvin cycle is _____.

Making Sugar -Using the ATP and NADPH made during the light reactions, carbon is reduced in the Calvin cycle and sugar is made.

In autumn, chlorophyll is degraded in the leaves of deciduous trees. Why do the leaves change color to shades of yellow, orange, or red?

Other pigments such as carotenoids are still present in the leaves.

How are cellular respiration and photosynthesis related to each other?

Photosynthesis is the opposite of cellular respiration.

Energized electrons from ____ are used to reduce NADP+.

Photosystem I

_____ splits water into 1/2 O2, H+, and e- .

Photosystem II splits water into 1/2 O2, H+, and e- .

Chlorophyll can be found in _____.

Photosystems I and II

What are the two stages of photosynthesis?

The light reactions and the Calvin Cycle.

Where does the light reaction occur?

The thylakoid

The energy that drives photosynthesis comes from which portion of sunlight? a)UV light b)Only light in the green wavelengths of the white light spectrum c)Light from the non-green wavelengths of the white light spectrum d)The entire spectrum of white light e)Both white light and UV light

c) Light from the non-green wavelengths of the white light spectrum

Carbon enters the cycle as CO2 and leaves as a sugar named

glyceraldehyde 3-phospate (G3P)

What kind of bond is formed when lithium and fluorine combine to form lithium fluoride?

ionic

In mitochondria, an electron transport chain pumps protons from the matrix into the intermembrane space, whereas in chloroplasts, an electron transport chain pumps protons from the ________.

stroma to the thylakoid

What is photosynthesis?

the process that converts solar energy into chemical energy

Where does the Calvin Cycle occur?

the stroma of the chloroplast

The light reactions of photosynthesis use _____ and produce _____.

water, NADPH