pH and the Scientific Method
Your book defines pH as the “measure of the relative acidity of a solution, ranging in value from 0 (most acidic) to 14 (most basic). pH stands for potential hydrogen and refers to the concentration of hydrogen ions.” (G-12) Living organisms (e.g., plants, animals, bacteria) require careful control of their internal pH, since they are sensitive to even small changes in pH. Homeostasis is the maintenance, by living organisms, of stable surroundings; this includes pH, as well as temperature, osmolarity, and a number of other environmental variables.
1. Explain how organisms that require a neutral environment survive and function despite metabolic activities that tend to shift pH toward either acidic or basic ends of the pH scale? Be specific!
You’ve read about the Scientific Method in our Unit 1 overview page and this unit’s lecture. The scientific method is used unconsciously by many people on a daily basis, for tasks such as cooking and budgeting. Understanding how to apply the scientific method to these seemingly non-scientific problems can be valuable in furthering one’s career and in making decisions. We talk about a hypothesis being used and tested, but a hypothesis is often confused with a prediction.
2. Explain what a hypothesis and a prediction are and how they are different.
3. Imagine that you notice that your neighbor’s lawn is lusher and greener than yours. You observe your neighbor for several units and it appears that he treats his lawn no different than you, except for the fact that he applies a fertilizer. Based on this observation, identify a testable hypothesis that explains your observation and provide at least one prediction based on your hypothesis.