Exam 10: Photosynthesis

Halobacterium has a photosynthetic membrane that appears purple. Its photosynthetic action spectrum is the inverse of the action spectrum for green plants (see figure). That is, the Halobacterium action spectrum has a peak where the green plant action spectrum has a trough. What wavelengths of light do the Halobacterium photosynthetic pigments absorb?

Which of the following statements is a correct distinction between autotrophs and heterotrophs?

What wavelength of light in the figure is most effective in driving photosynthesis?

Which of the following processes is directly associated with photosystem I?

A spaceship is designed to support animal life for a multiyear voyage to the outer planets of the solar system. Plants will be grown to provide oxygen and to recycle carbon dioxide. Since the spaceship will be too far from the sun for photosynthesis, an artificial light source will be needed. What wavelengths of light should be used to maximise plant growth with a minimum of energy expenditure?

The reducing power for Calvin cycle reactions is provided by which of the following molecules?

Which of the following processes occurs during the Calvin cycle?

Theodor W Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths of light. He added aerobic bacteria and then noted in which areas the bacteria congregated. He noted that the largest groups were found in the areas illuminated by the red and blue light. What did Engelmann conclude about the congregation of bacteria in the red and blue areas?

What are the products of cyclic electron flow during the light reactions of photosynthesis?

Which of the following statements correctly describes a distinction between autotrophs and heterotrophs?

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

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 ________.

Which of the following events accompanies absorption of energy by chlorophyll molecules of the reaction-centre complex?

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

P680+ is said to be the strongest biological oxidising agent. Given its function, why is this necessary?

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

In autotrophic bacteria, where is chlorophyll located?

What would be the expected effect on plants if the atmospheric CO₂ concentration was doubled?

As a research scientist, you measure the amount of ATP and NADPH consumed by the Calvin cycle in one hour. You find that 30,000 molecules of ATP were consumed, but only 20,000 molecules of NADPH were consumed. What is the source of the extra ATP molecules?

What is the function of the pigment molecules in a light-harvesting complex in the thylakoid membranes?