Biology I - Unit 2 - Chapter 8

What is the role of NADP+ in photosynthesis?

It is reduced and then carries electrons to the Calvin cycle.

Outputs of the Calvin Cycle (there are 3)

NADP+ ADP G3P

The most important role of pigments in photosynthesis is to __________.

capture light energy

n photosynthesis, plants use carbon from __________ to make sugar and other organic molecules.

carbon dioxide

According to the chemiosmotic hypothesis, what provides the energy that directly drives ATP synthesis?

Proton gradient

Which of the following reactions ensures that the Calvin cycle can make a continuous supply of glucose? Carbon fixation Production of G3P Production of 3-phosphoglycerate Regneration of RuBP

Regneration of RuBP

Which of the following does not occur during the Calvin cycle? Carbon fixation Release of oxygen Oxidation of NADPH Regeneration of the CO2 acceptor Consumption of ATP

Release of oxygen

Which process is most directly driven by light energy? reation of a pH gradient by pumping protons across the thylakoid membrane Carbon fixation in the stroma Removal of electrons from chlorophyll molecules Reduction of NADP+ molecules ATP synthesis

Removal of electrons from chlorophyll molecules

How is photosynthesis similar in C4 plants and CAM plants?

Rubisco in not the enzyme that catalyzes the initial fixation of carbon.

How does carbon dioxide enter the leaf?

Through the stomata

Chlorophyll molecules are in which part of the chloroplast?

Thylakoid membranes

Why are C4 plants more suited to hot climates than C3 plants?

Unlike C3 plants, they keep fixing carbon dioxide even when the concentration of carbon dioxide in the leaf is low.

Where do the electrons entering photosystem II come from?

Water

You could distinguish a granum from a crista because the granum, but not the crista, would __________.

have photosynthetic pigments

Photosystem II Functions: (there are 4)

oxidation of water reduction of electron transport chain between the two photosystems light absorbtion reduction of primary electron acceptor

In mechanism, photophosphorylation is most similar to __________.

oxidative phosphorylation in cellular respiration

Outputs of Light Reactions (there are 3)

oxygen ATP NADPH

The source of the oxygen produced by photosynthesis has been identified through experiments using radioactive tracers. The oxygen comes from __________.

water

Which of the following sequences correctly represents the flow of electrons during photosynthesis? H2O → NADPH → Calvin cycle NADPH → O2 → CO2 NADPH → chlorophyll → Calvin cycle H2O → photosystem I → photosystem II NADPH → electron transport chain → O

H2O → NADPH → Calvin cycle

Imputs of Light Reactions (there are 4)

light water ADP NADP+

A photon of which of these colors of light would carry the most energy?

Blue

What portion of the electromagnetic spectrum is most absorbed by the chlorophyll pigments in the thylakoid membranes?

Blue-violet and red light

Inputs of the Calvin Cycle (there are 3)

Carbon dioxide ATP NADPH

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.

False

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

False

The reactions of the Calvin cycle are not directly dependent on light, but they usually do not occur at night. Why?

The Calvin cycle requires products only produced when the photosystems are illuminated.

During photosynthesis, an electron transport chain transports __________.

electrons from photosystem II to photosystem I

Photosystem I Functions: (there are 4)

reduction of NADP+ oxidation of electron transport chain between the two photosystems light absorbtion reduction of primary electron acceptor

The Calvin cycle occurs in the __________.

stroma

Rubisco is __________.

the enzyme in C3 plants that first captures CO2 to begin the Calvin cycle

When chloroplast pigments absorb light, __________.

their electrons become excited

During photosynthesis in a eukaryotic cell, an electrochemical gradient is formed across the ___________.

thylakoid membrane