Is there a multiple choice or fill in the blank?
The answer is A) they provide a source of energy.
Answer:
As light intensity increases (distance between lamp and plant decreases) the volume of oxygen (or the rate of bubble production) increases. This indicates that the rate of photosynthesis increases with light intensity. However, at sufficiently high levels of light intensity, the rate oxygen evolution remains constant.
The answer is hydrogen bond between the complementary strands.
