Plants Practice Test

Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle?

• electrons and H+

• ATP and NADPH

• H2O and O2

• CO2 and glucose

When oxygen is released as a result of photosynthesis, it is a by-product of which of the following?

• the electron transfer system of photosystem I

• reducing NADP+

• chemiosmosis

• the electron transfer system of photosystem II

• splitting the water molecules

The reaction-center chlorophyll of photosystem I is known as P700 because

• there are 700 photosystem I components to each chloroplast.

• this pigment is best at absorbing light with a wavelength of 700 nm.

• there are 700 chlorophyll molecules in the center.

• the plastoquinone reflects light with a wavelength of 700 nm.

• it absorbs 700 photons per microsecond.

Generation of proton gradients across membranes occurs during

• respiration.

• both photosynthesis and respiration.

• photorespiration.

• neither photosynthesis nor respiration.

• photosynthesis.

What is the primary function of the Calvin cycle?

• transport RuBP out of the chloroplast

• use NADPH to release carbon dioxide

• split water and release oxygen

• use ATP to release carbon dioxide

• synthesize simple sugars from carbon dioxide

CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they

• use photosystems I and II at night.

• fix CO2 into sugars in the bundle-sheath cells.

• use the enzyme phosphofructokinase, which outcompetes rubisco for CO2.

• fix CO2 into pyruvate in the mesophyll cells.

• fix CO2 into organic acids during the night.

Which of the following does not occur during the Calvin cycle?

• carbon fixation

• release of oxygen

• regeneration of the CO2 acceptor

• oxidation of NADPH

• consumption of ATP

You are studying a plant from the arid southwestern United States. Which of the following adaptations is least likely to have evolved in response to water shortages?

• a thick waxy cuticle on the epidermis

• formation of a fibrous root system spread over a large area

• closing the stomata during the hottest time of the day

• development of large leaf surfaces to absorb water

• mycorrhizae associated with the root system

Which part of a plant absorbs most of the water and minerals taken up from the soil?

• taproots

• the thick parts of the roots near the base of the stem

• sections of the root that have secondary xylem

• root hairs

• storage roots

A person working with plants may remove apical dominance by doing which of the following?

• pruning

• transplanting

• fertilizing

• deep watering of the roots

• feeding the plants' nutrients