Question

a student designs an experiment to investigate how different light colors influence the rate of photosynthesis. the student places similar potted plants under four different colored lights (red, blue, green, and white), while keeping all other conditions the same. after one hour, the student measures the oxygen concentration in the air around each plant.

light color	plant height (cm)	oxygen concentration (ppm)
blue	47	20
green	50	7
white	48	12

which conclusion best explains how light color affects photosynthesis?

• white light reduces photosynthesis because it contains multiple wavelengths.
• green light is the most effective for photosynthesis because it is the color of plant leaves.
• all colors of light support photosynthesis equally because oxygen is produced regardless of plant height.
• red and blue light increase photosynthesis more than green light because the oxygen concentration is higher.

Explanation:

Photosynthesis rate can be inferred by oxygen concentration. Red and blue light result in higher oxygen concentrations compared to green light, indicating they promote photosynthesis more. White light contains multiple wavelengths and also has a relatively high - oxygen production. Green light is reflected by plants and is less effective for photosynthesis.

Answer:

Red and blue light promote photosynthesis more than green light because the oxygen concentration is higher.