*ch 8 practice questions

What products of light reactions of photosynthesis are used in the Calvin cycle?

ATP and NADPH

Which plants utilize a specialized carbon fixation enzyme and a unique cell type/organization to reduce the problems of photorespiration?

C4

Plants that show a pattern of stomatal opening and closing that is the reverse of C3 plants are called

CAM

In plants, the light-dependent reactions require

NADP+.

Jan Baptista van Helmont did an important experiment related to photosynthesis. He weighed a small willow tree and a pot of soil. Jan then planted the tree in the pot. Over the course of five years, he added only water to the pot. At the end of five years, he weighed the tree and found that it had gained 74.4 kg. He weighed the soil, and it was only 57 g less. What do the results of this specific experiment demonstrate about what is needed for a plant to grow and increase its mass?

Plants must be able to increase their mass using substances in addition to what is found in soil.

If a plant's stomata were always closed, how would this affect the plant's ability to make glucose?

Plants would make less sugar than normal.

If chlorophyll a is blocked from absorbing light, what would be the effect on the ability of the plant to do photosynthesis?

The plant will have a decreased ability to carry out light-dependent reactions.

As electrons travel from the primary electron acceptor in photosystem II down the electron transport chain to photosystem I, they drive the movement of protons from the stroma into the thylakoid compartment. Why is the development of this chemical gradient useful to photosynthesis?

The proton gradient can drive the production of ATP, which is needed for the light-independent reactions

At night, the Calvin cycle in a C3 plant

can still run as long as there is ATP, CO2, and NADPH present.

The role of the antenna complex in a photosystem is to

capture photons from sunlight.

Where do the carbon atoms in glucose come from?

carbon dioxide

In photosynthesis conducted by plants, ATP is made by

chemiosmosis

The light-independent reactions of photosynthesis are those that

convert CO2 into reduced molecules (sugars).

If the gene encoding the enzyme rubisco is mutated such that it is nonfunctional, the process that would be affected is the ability to

fix carbon.

CAM and C4 plants likely grow in what type of environment?

hot and arid

Molecules that absorb light are called

pigments

Inside the chloroplast, where are organic molecules made?

stroma

A photosystem channels the excitation energy gathered by absorption of light by any one of the pigment molecules to a specific reaction center chlorophyll, which in turn passes the energy to

the primary electron acceptor.

Most atmospheric oxygen comes from photosynthesis. From which molecules is the oxygen derived?

water

Illuminated chloroplasts deprived of carbon dioxide

will accumulate ATP, NADPH, and not produce glucose.