Help With Biology 1 Please ? (7 Questions)

13. Tami is growing a species of algae in a test tube containing a trace amount of phosphate. The algae multiply until all the phosphate runs out. If Tami adds more phosphate, the algae will start multiplying again. What is the role of the phosphate in this system?
a. Consumer
b. Limiting factor
c. Constant
d. Biotic factor


14. In the eukaryotic cell, organelles called peroxisomes contain an enzyme that turns hydrogen peroxide (H2O2) into water (H2O). Suppose a biologist is measuring how temperature affects the rate at which the enzyme converts a quantity of H2O2 into water. Which of the following tools should the biologist use to make her measurements?
a. Microscope and thermometer
b. Pipette and meterstick
c. Stopwatch and graduated cylinder
d. Thermometer and stopwatch


15. Dr. Ivy wants to investigate the effect of oxygen concentration on the rate of cellular respiration in a plant species. Dr. Ivy exposed several plants to different concentrations of gaseous oxygen (O2). He will then measure the amount of a particular gas produced by the plants. Which method should Dr. Ivy use to collect data in this experiment?
a. Use a digital balance to measure the amount of oxygen that the plants consume
b. Use a digital balance to measure the amount of carbon dioxide that the plants give off
c. Use a stopwatch to measure the amount of carbon dioxide that the plants produce at regular time intervals
d. Use a stopwatch to measure the amount of carbon dioxide that the plants consume at regular intervals


16. What is the primary purpose of cellular respiration?
a. To use sunlight to produse food molecules
b. To release energy from food molecules
c. To remove carbon dioxide from an organism
d. To bring oxygen into an organism


17. Which of the following correctly describes a major difference between a plant cell and an animal cell?