INDEPENDENT & DEPENDENT VARIABLE PRACTICE 2. You want to measure the effect of different amounts of oxygen on the rate of yeast growth. What is the dependent variable? 3. Orchids were studied to determine if the amount of humidity affected the flowering of these plants. Which of these was the independent variable in this study? 4. You want to test a new drug that supposedly prevents sneezing in people allergic to grass. What is the dependent variable? 5. You want to test a new drug that supposedly prevents sneezing in people allergic to grass. What is the independent variable? 6. You think that a certain part of your brain is important in memory. To test this, you will remove this part of the brain from rats and see if they remember how to get through the maze. What is the independent variable in this experiment? 7. A florist wants to see if Product X will extend the life of cut flowers so that they last longer. What is the dependent variable? 8. You want to measure the effect of different amounts of oxygen on the rate of yeast growth. What is the independent variable? 9. Harvester ants often strip a bush of all of its leaves. Some people believe this helps the plant grow thicker, healthier stems. In an experiment, a student stripped off all the leaves from a set of plants. In a second set of identical plants, the student allowed ants to strip off the plants’ leaves. In order to improve this experimental design, it is most important to add a set of plants — 10. You want to see if playing music makes plants grow taller. What is the dependent variable in this experiment? 11. A soap manufacturer wants to prove that their detergent works better to remove tough stains. What is the dependent variable? 12. A soap manufacturer wants to prove that their detergent works better to remove tough stains. What is the independent variable? 13. A florist wants to see if Product X will extend the life of cut flowers so that they last longer. What is the independent variable? INDEPENDENT & DEPENDENT VARIABLE PRACTICE 14. An entomologist (bug scientist) wants to determine if temperature changes how many times a cricket chirps. What is the independent variable? 15. An entomologist (bug scientist) wants to determine if temperature changes how many times a cricket chirps. What is the dependent variable? 16. You want to see if playing music makes plants grow taller. What is the independent variable in this experiment?