Research Process

Question Every scientific investigation begins with the question that the scientist wants to answer. The questions are based on observations or on information gained through previous research, or on a combination of both. Discuss the following questions with your lab group and decide which of them you think can answered scientifically. Groups A, 3, 5, & 7 What is in the black box? Are serial killers evil by nature? Groups 2, 4, 6, & 8 What is the best recipe for chocolate chip cookies? How can the maximum yield (tons/acre) be obtained form a peanut field? A question can be answered scientifically when…

Hypothesis A hypothesis is a possible answer to the question. A hypothesis is only usable if an experiment can be performed to test the hypothesis. Moore than one hypothesis may be formulated to answer a question. We cannot prove a hypothesis true, we can only support the hypothesis with evidence form the investigation. Discuss the following hypotheses with your lab group and decide which of them would be a useful hypothesis (can an experiment be performed to test it.) Give the reason for your answer. Groups A, 3, 5, & 7 Plants absorb water through their leaves as well as through their roots. More people behave immorally when there is a full moon than at any other time of the month. Groups 2, 4, 6, & 8 Dogs are happy when you feed them steak. An active volcano can be prevented from erupting by throwing a cat into it during each full moon. Prediction The prediction states the expected results if the hypothesis is correct. Deductive reasoning (if…then logic) is used. For example, if the black box contains a thumb tack and a paper clip, then when I shake the black box it will sound the same as a box with a thumb tack and a paper clip.

Tests: Experiments are performed and data is collected to test the hypothesis and answer the question. Tests must be repeated multiple times for the results to be valid. A controlled experiment is an experiment that is done where only one factor (variable) is changed. The results are compared to a control experiment where the variable is not changed or it is not present. There are two types of variables: 1. Dependent variable – This is what the investigator measures, counts or records. 2. Independent variable – what the investigator deliberately varies during the experiment. Example: in the black box experiment the objects placed in the box where the independent variables, and the sound the box made when shaken was the dependent variable. In your lab group identify the dependent variable (DV) and independent variables (IV) in the following examples. Groups 2, 4, 6, & 8 The diversity of fish species is calculated for a coastal area before and after and oil spill. Rats are kept at different temperatures for 6 weeks. Percent weight gain is recorded. Groups A, 3, 5, & 7 The height of bean plants is recorded daily for 2 weeks Light absorption by a pigment is measured for red, blue, green, and yellow light.

Summary Diagram Conclusions Initial observation Define Problem New Hypothesis &/ or Experiments Conclusions Conclusions are based on current results only and reflect the best evidence available at the time. A conclusion is not valid unless data from an experiment is provided to support it. Communication of Findings Scientists share their findings with others by writing research articles, presenting at scientific meetings, and by a personal communication. It is important to remember that scientific knowledge is an accumulation of evidence in support of a hypothesis. Future research may fin that a hypothesis is no longer supported Summary Diagram

multiple tests Support Theory Formed if evidence from multiple tests Support an overarching idea