(These are Biology Short Answer Questions. Please make sure the answers don’t get too lengthy, short and compact answers are best, as long as the question is fully answered. Thanks :))
1. Juan and Hailey heard that spraying vinegar on plant leaves will prevent caterpillars from eating the leaves. They decide to design an experiment to see if this is true. They mark a line down the middle of the garden and then spray the plants on one side of that garden with vinegar. For the next 10 days, they spray the same side of the garden with vinegar and observe how many caterpillars they can count on each side of the line. After 10 days, if there were more caterpillars on the non-vinegar side of the garden than on the side sprayed with vinegar, Juan and Hailey will conclude that vinegar does prevent caterpillars from eating leaves.
(a) Identify THREE variables that were not specifically controlled in the experimental design.
(b) For each of these variables, describe how they might have affected the outcome of Juan and Hailey’s experiment.
(c) For each of the variables listed, suggest a way to better control them if the experiment were to be repeated.
2. A group of scientists studying vegetation in a mountain range observe that a certain flowering plant grows taller at lower elevations and shorter at higher elevations. Assuming the two populations of plants are genetically similar, those height variations are most likely due to developmental flexibility that allows the plants to assume tall or short growth forms.
(a) Identify THREE biotic or abiotic factors that could differ at high and low elevations and cause the difference in plant height.
(b) Using one of the factors listed in part (a) as an independent variable, write a hypothesis that proposes how this variable could cause the difference in plant height at high and low elevations.
(c) You are given seeds for this species of plant. Design a procedure for a controlled experiment to test your hypothesis.
(d) Describe the results that would support your proposed hypothesis, and the results that would refute your hypothesis