Question

calhoun, miya bio sci sem 1 asst 1 cherokee sc 2025 - 2026 photosynthesis in action a group of students designs an experiment to study photosynthesis in a hydrilla plant. the students place the plant in a beaker filled with pond water and trapped inside a glass funnel. the students collect data after two hours. figure 1 shows a diagram of the experiment. figure 1. experiment diagram table 1 shows the results of the experiment. table 1. experiment results observation description 1. the amount of air at the top of the test tube increases based on graph 1, how would blocking light affect the oxygen levels in the lake over time if hydrilla were the dominant plant species? oxygen levels would decrease severely because hydrilla stops both photosynthesis and respiration. oxygen levels would decrease moderately as hydrilla reduces photosynthesis while continuing respiration. oxygen levels would increase moderately as hydrilla reduces photosynthesis while continuing respiration. oxygen levels would increase severely because hydrilla stops both photosynthesis and respiration.

Explanation:

Photosynthesis in plants like hydrilla produces oxygen using light. Blocking light stops photosynthesis while respiration (which consumes oxygen) continues. So oxygen levels decrease. Hydrilla doesn't stop respiration or photosynthesis in normal - light conditions, but without light, photosynthesis halts.

Answer:

Oxygen levels would decrease moderately as hydrilla reduces photosynthesis while continuing respiration.