Final answer:
The independent variable in the photosynthesis experiment is the concentration of bicarbonate solution, which is varied to observe its effect on the rate of photosynthesis.
Step-by-step explanation:
The independent variable in this experiment is the concentration of bicarbonate solution. The independent variable is defined as the variable that is changed or controlled in a scientific experiment to test the effects on the dependent variable. In this case, the student changes the concentration of the bicarbonate solution to measure the effect on the rate of photosynthesis, which is observed through bubble production and the number of leaf disks that float after exposure to light.
In this experiment, the independent variable is the concentration of the bicarbonate solution. The independent variable is the factor manipulated or controlled by the experimenter to observe its effect on the dependent variable. In the context of this experiment, the student is intentionally altering the concentration of the bicarbonate solution. This manipulation serves as a means to investigate and measure the impact of bicarbonate concentration on the rate of photosynthesis.
The dependent variable in this experiment is the rate of photosynthesis, which is observed through specific indicators such as bubble production and the number of leaf disks that float after exposure to light. By systematically changing the independent variable, the concentration of the bicarbonate solution, the experimenter can analyze how variations in this factor influence the dependent variable, providing valuable insights into the relationship between bicarbonate concentration and photosynthetic rates.