The proteins of the electron transport chain active in the light-dependent reactions _____.
are membrane proteins present in the thylakoid
Which of the following is a difference between chlorophyll a and chlorophyll b?
Chlorophyll a and b absorb light energy at slightly different wavelengths.
Why are there several structurally different pigments in the reaction centers of photosystems?
This setup enables the plant to absorb light energy of a variety of wavelengths.
If pigments from a particular species of plant are extracted and subjected to paper chromatography, which of the following is the most believable result?
Paper chromatography would separate the pigments from a particular plant into several bands.
The absorption spectrum of a plant shows what wavelengths of light the plant absorbs. The absorption spectrum depends on _____.
the wavelengths of light to which the plant's pigments respond
Which term describes ATP production resulting from the capture of light energy by chlorophyll?
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.
According to the chemiosmotic hypothesis, what provides the energy that directly drives ATP synthesis?
True or false? The region of ATP synthase that catalyzes the production of ATP from ADP and inorganic phosphate spans the chloroplast membrane.
Chloroplast membrane vesicles are equilibrated in a simple solution of pH 5. The solution is then adjusted to pH 8. Which of the following conclusions can be drawn from these experimental conditions?
ATP will not be produced because there is no ADP and inorganic phosphate in the solution.
_____ releases energy that is used to pump hydrogen ions from the stroma into the thylakoid compartment.
The energy released as electrons are passed along the electron transport chain is used to pump protons into the thylakoid compartment.
Energized electrons from ____ enter an electron transport chain and are then used to reduce NADP+.
Energized electrons from photosystem I are used to reduce NADP+.
Plastoquinone (PQ), an electron carrier of small molecular weight, is found in the electron transport chain associated with photosystem II. If PQ is not directly anchored to other membrane or cytoplasmic structures, it is probably _____.
mobile in the thylakoid membrane
What is the importance of the light-independent reactions in terms of carbon flow in the biosphere
The light-independent reactions turn CO2, a gas, into usable carbon in the form of sugars.
What is the biological significance of the light-independent reactions of photosynthesis
They convert carbon dioxide to sugar.
Which of the following statements best describes the relationship between the light-dependent and light-independent reactions of photosynthesis?
The light-independent reactions release energy, and the light-dependent reactions require energy.
The light-dependent reactions pass electrons through an electron transport chain to the light-independent reactions.
The light-dependent reactions produce carbon dioxide, which is then used by the light-independent reactions.
XThe light-dependent reactions produce ATP and NADPH, which are then used by the light-independent reactions.
Which of the following reactions ensures that the Calvin cycle can make a continuous supply of glucose?
Regneration of RuBP
C4 plants differ from C3 and CAM plants in that C4 plants _____.
transfer fixed carbon dioxide to cells in which the Calvin cycle occurs
In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?
How are the light-dependent and light-independent reactions of photosynthesis related?
The products of light-dependent reactions are used in light-independent reactions.
What is the main purpose of the light-dependent reactions of photosynthesis?
to produce NADPH and ATP
Data suggest that rubisco (ribulose-1,5-bisphosphate carboxylase) makes up 10% of the total protein found in spinach leaves. Research elucidating the structure of rubisco shows that it has four active sites. Why, with four active sites, might there be such a large concentration of rubisco in plant matter?
Rubisco is a very slow enzyme; what it lacks in speed, it makes up in quantity.