Question

Energy enters most ecosystems through the light-dependent reaction of photosynthesis. Describe what happens during the light-dependent reaction. (5)

a) The light-dependent reaction involves the conversion of glucose into oxygen and water.
b) During the light-dependent reaction, oxygen is converted into glucose.
c) The light-dependent reaction produces ATP and NADPH using light energy and water, releasing oxygen as a byproduct.
d) In the light-dependent reaction, carbon dioxide is transformed into organic molecules using energy from sunlight.

Answer 1

During the light-dependent reactions of photosynthesis, chlorophyll absorbs sunlight and converts it into chemical energy, producing ATP and NADPH, and releasing oxygen.

Step-by-step explanation:

Energy enters most ecosystems through photosynthesis, which occurs in two main stages: the light-dependent reactions and the Calvin cycle. During the light-dependent reactions, chlorophyll within the thylakoid membranes of the chloroplast absorbs energy from sunlight. This energy is used to split water molecules (H₂O), releasing oxygen as a byproduct and converting light energy into chemical energy in the form of ATP and NADPH. These energy carriers, ATP and NADPH, are then utilized in the Calvin cycle to synthesize glucose from carbon dioxide (CO₂).

Thus, the correct answer to what happens during the light-dependent reaction is: c) The light-dependent reaction produces ATP and NADPH using light energy and water, releasing oxygen as a byproduct.