Students Conducted an Experiment to Determine the Effect of Light

question 49

Multiple Choice

Students conducted an experiment to determine the effect of light intensity on the rate of photosynthesis. They punched 40 leaf disks from spinach leaves and used a syringe partially filled with water to pull the gases from the leaf disks so that all leaf disks sunk to the bottom of the syringe. Ten leaf disks from the syringe were placed in each of four cups and covered with 50 ml of the solutions as indicated below. All leaf disks were resting on the bottom of the cups when the experiment began. The volume of liquid in each cup and the temperature of the solutions were held constant. All cups were placed 0.5 meters from the designated light source. A large beaker of water was placed between the light and the cups to act as a heat sink to prevent a change in temperature. At the end of 10 minutes, the number of disks floating in each cup was recorded.

Use your knowledge of the mechanism of photosynthesis and the data presented in the chart to determine which of the statements is a correct explanation for the students' data.

• A) Cup 1 had a low rate of photosynthesis because 0.5 grams of baking soda did not provide a sufficient amount of CO₂.
• B) Cup 2 had the highest rate of photosynthesis because it had the highest ratio of disks floating to wattage of light.
• C) Cup 3 had the same rate of photosynthesis as Cup 1 because they had the same ratio of disks floating to wattage of light.
• D) Cup 4 had the lowest rate of photosynthesis because it had the least CO₂.

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Definitions:

Stock Prices

The current market price at which shares of a company are bought and sold.

Leverage

Use of borrowed capital for investment with the aim to multiply the potential returns, while also increasing the risk of loss.

Independence Hypothesis

In capital structure theory, the original restrictive model by Modigliani and Miller that shows stock price to be independent of capital structure.

Modigliani

Refers to Franco Modigliani, an economist known for his work on the Modigliani-Miller theorem, which addresses the valuation of stocks and corporate taxes.