Exam 7: Photosynthesis: Using Light to Make Food

-If the interior of the thylakoid were not a sealed compartment, ________.

In photosynthesis, an H⁺ ion gradient forms across the ________.

-Refer to the accompanying figure. What is TRUE regarding the behavior of a chlorophyll molecule as it absorbs a photon?

-The light reactions are generally presented in zig-zag patterns, as shown in the accompanying figure which has an implied amount of energy on the vertical axis. What is the significance of the primary electron receptor shown at position 2 being slightly higher than the primary electron receptor shown at position 3?

Scientists are working to create a better biofuel factory through which processes?

When a molecule releases energy gained by absorption of a photon, in what form may that energy be released?

Some plant species require shaded conditions while other plant species require bright sunlight. Shade tolerance is best related to which of these characteristics?

Plant photosystems are located in ________.

-The first step of the Calvin cycle is the incorporation of ________ into ________.

The Calvin cycle makes direct use of ________ to make ________.

Please refer to the following art to answer the following questions. -How many times must the Calvin cycle turn for the plant cell to be able to produce one molecule of glucose?

Which molecule is the source of electrons for the light reactions?

Which equation best summarizes photosynthesis?

The Calvin cycle requires ________ and ________ from the light reactions in order to operate.

A ________ is an autotroph

The light reactions of photosynthesis take place ________.

-If an herbicide blocked the Calvin cycle before the generation of G3P, what would happen?

When looking at a pigmented object, the color we see is the wavelengths that ________.

________ is the source of the oxygen gas released by a photosystem.

Scenario You work for a company selling tropical rain forest plants commonly found in the understory of the forest. These plants are shade tolerant and can be grown indoors because they require low light. Your employer wants you to find out what is the best type of light to maximize growth of these understory plants. Using a full spectrum of natural light would cause these plants to die because they are a shade-tolerant plant species. From your biology class, you recall that the light-dependent reactions of photosynthesis involve pigment molecules that absorb light of specific wavelengths. You also remember the experiments done by the German biologist Theodor Engelmann, in which he separated light using a prism into different wavelengths and then determined which wavelengths were best for promoting photosynthesis in the algae species he was examining. Your goal is to determine which wavelengths (colors)of light are best for promoting photosynthesis to enhance growth in your species of plant. To achieve this, you grew your plants under different wavelengths of light and measured their growth rates. The wavelengths were measured in nanometers (nm), and the growth rate was measured in millimeters per day (mm/day). The data you collected are as follows: Make a bar graph plotting growth rates on the y-axis and wavelengths of light on the x-axis. Referring to your graph, answer the following questions: -Which wavelength of light is the LEAST useful to your plants' growth?