Question

If Engelmann's experiment was repeated without passing light through a prism, then

• A. no difference in result is observed
• B. bacteria will evenly distribute along the length of the algae
• C. number of bacteria would decrease due to increase in carbon dioxide
• D. number of bacteria would increase due to decrease in carbon dioxide

Answer 1

The correct option is B bacteria will evenly distribute along the length of the algae

Engelmann performed his experiment by placing oxygen loving bacteria on the alga and illuminating it with light that had been passed through a prism.
He observed that bacteria were concentrated in the area where red and blue light fell.
Their clumping allowed him to see which regions had the highest concentration of oxygen.
Therefore, the bacteria accumulated in the regions of red and violet light, as these wavelengths of light generated the most photosynthetic activity.
If light is not passed through a prism, all regions of the algae generates the same photosynthetic activity and bacteria will evenly distribute along the length of the algae.