A student used the dimmest setting on a light microscope to observe a euglena and an amoeba. The student shined a narrow beam of light at the top of the cover slip. She observed that the euglena swam up toward the light but the amoeba did not. She knew the amoeba was alive because it slowly changed shape while she watched. What inference should the student draw from her observation?
A: An amoeba is unable to respond to light.

What is a benefit of the regulation of gene expression?
A: conservation of cell resources

How are green plants an important part of the carbon dioxide-oxygen cycle?
A: They release oxygen into the air.

An increase in phosphate levels in a lake increases the population of algae in the lake. Increased algae blocks sunlight into the lake and results in a decrease in dissolved oxygen in the lake's water. Which of the following should be expected as a result?
A:
Fish populations in the lake decline.