Question

part a
students investigate how light intensity affects the rate of photosynthesis in an aquatic plant.
their setup is shown in the diagram.
light intensity investigation
the students place a light at different distances from the plant and record the number of bubbles
produced. their data are shown in the table.
student data
which inference is supported by the data?
a the plant produces more oxygen as light intensity increases.
b the plant takes in more water when the light intensity decreases.
c the plant requires more energy for photosynthesis at lower light intensities.
⑥ the plant needs less carbon dioxide for photosynthesis at higher light intensities

Explanation:

• In photosynthesis, oxygen is a by - product. The number of bubbles produced per minute can be an indicator of the rate of photosynthesis (and thus oxygen production).
• As the distance from the light (which is inversely related to light intensity, \(I\propto\frac{1}{d^{2}}\), where \(d\) is the distance) decreases (light intensity increases), the number of bubbles (which we assume to be oxygen bubbles) increases. For example, at \(d = 0.1m\) (higher light intensity) there are 124 bubbles per minute, and at \(d=0.5m\) (lower light intensity) there are 6 bubbles per minute.
• Option B: There is no data or indication in the experiment about water intake. The experiment is about light intensity and bubble (assumed oxygen) production.
• Option C: There is no information in the data about the energy requirements of the plant for photosynthesis at different light intensities. The data only shows the relationship between light distance (related to intensity) and bubble production.
• Option D: There is no data provided about carbon - dioxide requirements at different light intensities. The focus of the data is on bubble production (related to oxygen) and light distance.

Answer:

A. The plant produces more oxygen as light intensity increases.