Biol&211 - Lab 1 Pre-Lab Assesment

You do not need to pause to record your data as you perform your experiment. You can go back and estimate the values when the experiment is complete. True or False

False

If you wanted to test whether or not a particular pain reliever was effective in the general population, you would need to design an experiment with an experimental group and a control group. What should be the only difference between these two groups?

Treatment: The experimental group should get the pain reliever, and the control group should get a placebo Explanation: The control group is the group that received the independent variable. A placebo won't do anything to relieve pain, thus the group taking the placebo would be the control group because their pain levels would be unchanged.

Match the action to the appropriate phase of the scientific method. 1. draw graphs, evaluate the hypothesis 2. carry out the strategy, collect measurements 3. formulate a hypothesis and create a strategy 4. document results

Hypothesis - 3 Experiment - 2 Analysis - 1 Report - 4 Exlanation: The scientific method starts with a hypothesis and an idea of how to test that hypothesis. During the experiment, you could carry out the formed strategy and collect measurements/data. In analysis, data is examined, and graphs can be used for a visual representation of the findings. Documenting the results would occur when you report your findings.

Before you begin a scientific experiment, you should (Select all that apply) -state a hypothesis -report on the results -decide on a strategy - record the data

state a hypothesis decide on a strategy Explanation: To start an experiment you must have a hypothesis and a strategy. During the experiment you will record data collected and after you would report the results.

When determining the scope of an experiment, you need to consider (Select all that apply) -which data you will collect and plot. -the outcome you will investigate. -what results to report. -the factor that will vary

the outcome you will investigate the factor that will vary Explanation: When determining how to test a hypothesis, you need to understand what outcome you are testing for; for example, in the pillbug experiment, you were testing to see if the pillbug would choose the chamber with the cornstarch. You also need to know what factors will vary; again, with the pillbug experiment, the variables were the cornstarch and the sand. Knowing the pillbugs weren't repelled from the sand you could surmise the movement to the cornstarch vs sand was caused by wanting to go into that chamber and not because they were repelled by the sand in the opposing chamber.

Some students consume large amounts of caffeinated drinks to help them stay alert when studying. You notice that many who engage in this practice seem to do poorly on exams. Suppose you want to investigate the relationship between caffeine consumption and exam performance. Which of the following statements would be an appropriate hypothesis?

Students who consume large amounts of caffeine while studying have lower exam scores than students that consume less caffeine while studying. Explanation: A hypothesis is a tentative explanation for a phenomenon that can be tested and then supported or falsified based upon the results. To test the hypothesis, you would compare the exam scores of students who drink large amounts of caffeine while studying to those who do not. If the students who consume more caffeine have significantly lower scores, then your hypothesis is supported. Otherwise, the hypothesis is falsified. The statement that one should avoid consuming too much caffeine while studying is a recommendation, not a hypothesis. The statement that caffeine increases alertness but also increases anxiety would have to be tested more directly rather than looking just at exam scores. The statement that many students consume large amounts of caffeine caffeine while studying to try to improve their exam scores is an observation that could contribute to a hypothesis about why students are choosing to drink caffeine during study sessions, but it doesn't directly state a way to investigate the relationship between caffeine consumption and exam performance. Too much caffeine is harmful to your health is a conclusion that has been reached by some scientific studies; it is not, however, a hypothesis that is appropriate to this experimental design.

Imagine that you wish to compare two different diets that will be fed to tadpoles raised in a lab. One diet is a meat-based fish food, and the other is the traditional diet of boiled lettuce. You want to see if the meat-based diet will be associated with an increase in the average weight of the tadpoles. In your experiment you keep all other factors, such as tadpole density per pan, temperature, pH, and the amount of food the same. The only difference between your control and experimental groups is the type of food the tadpoles receive.

Tadpoles will be larger if fed a meat-based diet. Explanation: A good hypothesis is one that makes a prediction based on information known and predicts the behavior based off an independent (and testable) variable (there should only be one). The independent variable here is the type of food.

When utilizing the scientific method, there are two types of variables. They are

dependent and independent

Imagine that you wish to compare two different diets that will be fed to tadpoles raised in a lab. One diet is a meat-based fish food, and the other is the traditional diet of boiled lettuce. You want to see if the meat-based diet will be associated with an increase in the average weight of the tadpoles. In your experiment you keep all other factors, such as tadpole density per pan, temperature, pH, and the amount of food the same. The only difference between your control and experimental groups is the type of food the tadpoles receive. What is the independent variable for the tadpole diet experiment?

diet Explanation: The independent variable is the group that is being examined.

If the hypothesis in a scientific experiment is not supported, the experiment is considered a complete failure and must be repeated until a satisfactory outcome is reached. True or Flase

false Explanation: If a hypothesis is not supported, you have still learned important information form the experiment. That information should be recorded and shared in the Report phase.

When graphing your data, it is important to

place the dependent variable on the Y-axis.

When graphing your data, it is important that you

place the independent variable on the X-axis.