Which experimental procedure would provide the best evidence for the effect of light on plant growth?
The best experimental procedure to provide evidence for the effect of light on plant growth would be to conduct a controlled experiment where plants are grown under different light conditions and their growth is measured and compared.
Specifically, the experiment could be designed as follows:
1. Select a group of identical plant species, such as easily grown herbs or small flowering plants.
2. Divide the plants into several groups, with each group representing a different light condition. For example, one group can be exposed to natural sunlight, another group to artificial light with a specific spectrum, and a third group to complete darkness.
3. Ensure that all other factors that can affect plant growth, such as temperature, humidity, and watering, are kept constant for all groups.
4. Measure and record growth parameters such as plant height, leaf count, leaf area, and biomass at regular intervals.
5. Repeat the experiment multiple times to ensure reliability and obtain statistically significant results.
6. Analyze the data collected and compare the growth of plants under different light conditions.
7. Draw conclusions based on the results obtained and determine the effect of light on plant growth.
By conducting this type of experiment, scientists can directly observe and measure the impact of light on plant growth while effectively controlling for other influencing factors.