Unit 5b Test Corrections SP24

Bonus: A group of students are conducting an experiment on Elodea canadensis, a species of aquatic plant. In order to test the effect of light intensity on the rate of photosynthesis, they place each Elodea canadensis plant into an aquarium tank and place each tank at a different distance from a light source. After a few minutes, oxygen bubbles begin to form in each of the tanks. The students count the number of oxygen bubbles released during a \[5\] minute period for each tank. The results of their experiment are shown below. Which of the following conclusions is best supported by the results of the experiment?

• As light intensity increases, the production of photosynthetic products remains constant.
• As light intensity increases, the production of photosynthetic products decreases.
• As light intensity decreases, the production of photosynthetic products decreases.
• As light intensity decreases, the production of photosynthetic products remains constant.

Bonus: Name the 2 main reactions in photosynthesis:

Bonus: Which of the following best indicates that the light reactions of photosynthesis have completed and that the Calvin cycle has begun?

• An electrochemical gradient forms across the thylakoid membrane.
• ATP and NADPH accumulate in the stroma.
• A high concentration of carbohydrates is found in the thylakoid lumen.
• Electrons are transferred across the electron transport chain (ETC) on the thylakoid membrane.

Bonus: RuBisCO catalyzes the joining of carbon dioxide with RuBP during carbon fixation. In an experiment, researchers apply a toxin to a plant cell that inhibits RuBisCO. Which of the following explains the most likely effect this toxin will have on the Calvin cycle?

• Excited electrons will not be transferred across the electron transport chain.
• Carbon and oxygen will not be released after the breakdown of carbon dioxide.
• Carbon dioxide will not be converted into carbohydrates.

1. Energy is released from ATP when...

• a. a third phosphate group is added and a bond forms between the second and third phosphate group.
• b. adenine bonds to ribose.
• c. ATP is exposed to sunlight.
• d. the bond between the second and third phosphate is broken.

11. Most plants appear green because chlorophyll...

• a. absorbs green light.
• b. absorbs violet light.
• c. reflects green light.
• d. reflects violet light.

23. Chloroplasts are organelles, compartments within cells, that help plant cells harness solar energy and produce sugar molecules. Cells within plants are specialized; groups of similar cells form tissues, or layers of cells with different functions. Some cell types have more chloroplasts than others. A botanist is interested in learning more about the cell types within a Norway Spruce Tree. She collects cells from different parts of the pine needle and the tree and uses 3D imaging technology to measure the number of chloroplasts in each cell. For each type, she counts the chloroplasts in 20 individual cells. The data is shown in the graph. Which cell type has the most chloroplasts per cell?

• a. mesophyll
• b. cuticle
• c. epidermis
• d. root

7. Organisms, such as plants, that make their own food are called...

• autotrophs
• heterotrophs
• thylakoids
• pigments

10. Which statement best describes the biological process of photosynthesis?

• Light energy is transformed into chemical energy and oxygen is released.
• Light energy is transformed into chemical energy and carbon dioxide is released.
• Chemical energy is transformed into light energy and carbon dioxide is released.
• Chemical energy is transformed into light energy and oxygen is released.

11. The process of photosynthesis can be represented by the chemical formula...

• 6CO2 + C6H12O6 --> 6O2 + 6H2O + Sunlight
• Energy + 6CO2 + 6O2 --> C6H12O6 + 6H2O
• Sunlight + 6CO2 + 6H20 --> C6H12O6 + 6O2
• C6H12O6 + 6O2 --> 6CO2 + 6H2O + Energy