Question

The chloroplasts of flowering land plants typically contain at least two photosynthetic pigments, chlorophyll a and chlorophyll b, that differ in the wavelengths of light they absorb. The synthesis of chlorophyll pigments from precursor molecules is a process that involves many sequential enzyme-catalyzed steps. Researchers studied the growth and photosynthetic ability of a plant that contained a mutant form of one of the enzymes required for chlorophyll biosynthesis.
a. Describe the effect on chlorophyll-containing photosystems when the chlorophyll molecules absorb photons of light.
b. Identify an appropriate control that the researchers should use when they study the growth and photosynthetic ability of the plant with the mutant enzyme.
c. Scientists claim that a plant that has more than one type of photosynthetic pigment has greater fitness than a plant that has only one type of photosynthetic pigment. Provide reasoning to justify this claim.

Answer 1

Answer:

a. In chlorophyll photosystems, the photons excite electrons that are transferred from donor to acceptor molecules in a process that involves oxidation-reduction reactions

b. As negative controls could be produced targeted mutations in genes encoding for enzymes that are not involved in the growth and in the photosynthetic activity

c. The plants that have many classes of photosynthetic pigments absorb light in different ranges of the visible spectrum, thereby it may confer an adaptive advantage to these plants