1 The Methods of Biology Chapter 1.2

2 Scientific Methods

3 steps scientists use in which a problem is identified, relevant data are gathered, a hypothesis is formulated and tested scientific methods

4

5 An old way to remember

6 Induction is usually described as moving from the specific to the general, while deduction begins with the general and ends with the specific (Example below) Adam: I've noticed previously that every time I kick a ball up, it comes back down, so I guess this next time when I kick it up, it will come back down, too. Rick: That's Newton's Law. Everything that goes up must come down. And so, if you kick the ball up, it must come down. Scientists most commonly use inductive reasoning Inductive vs Deductive reasoning

7 Observation five senses Employing your five senses to perceive objects or events

8 Asking a Question Based on observations; one or more questions are generated

9 Forming a Hypothesis testable A statement is testable if evidence can be collected that either does or doesn’t support it It can never be proven beyond doubt refined and revised or discarded Often must be refined and revised or discarded

10 The Hypothesis --- An explanation for a question or problem than can be formally tested. An explanation for a question or problem than can be formally tested. Is a statement made in advance that states the results that will be obtained from testing the hypothesis Is a statement made in advance that states the results that will be obtained from testing the hypothesis “if- then” statement Often written in the form of an “if- then” statement

Copyright Cmassengale11 Experimenting Testing a hypothesis Testing a hypothesis or prediction is done with an experiment. controlled conditions By gathering data under controlled conditions – conducting a controlled experiment control grou experimental group Based on a comparison of a control group with an experimental group

12 procedure that tests a hypothesis by collecting information under controlled conditions experiment

13 in an experiment; the standard in which all of the conditions are kept the same. control

14 in an experiment; the condition that is changed because it affects the outcome of the experiment independent variable

15 in an experiment; the condition that results from changes in the independent variable dependent variable

except for one factor independent variable Both groups are identical except for one factor (independent variable) dependent variable Observations and measurements are taken for a particular factor (dependent variable) in both groups Driven by or results from independent variable 16

Measuring quantitative data numbers qualitative data Involves quantitative data that can be measured in numbers &/or qualitative data information that isn’t numbers Sampling sample represent the entire population Technique of using a sample – a small part – to represent the entire population 17

18 information obtained from experiments data

19 Organizing Data Involves placing observations and measurement (data) in order Graphs, charts, tables, or maps Graphs, charts, tables, or maps

20 Experiments that result in counts or measurements – numerical data quantitative research

21 experiments that result in observational data with written descriptions (how something behaves) descriptive research

22 Analyzing Data Collected and organized data must be analyzed determining whether data are reliable or whether they support or do not support a hypothesis Process of determining whether data are reliable or whether they support or do not support a hypothesis or prediction

23 Conclusion Conclusions are made on the basis of facts, not observations drawn from data Often drawn from data gathered from a study or experiment support the hypothesis Should support the hypothesis re-testable Should be re-testable

24 Communication share the results of their studies Scientists must share the results of their studies with other scientists (peers) Publishjournals Publish findings in journals scientific meetings Present their findings at scientific meetings unbiased Scientists must be unbiased Should not tamper with their data Only publish & report tested & proven ideas

Communication Sharing of information Sharing of information is essential to scientific process verification Subject to examination and verification by other scientists Allows scientists to build on the work of others 25

26 Theories theory A theory may be formed after many related hypotheses have been tested and supported with experimental evidence broad and comprehensive statement of what is thought to be true A broad and comprehensive statement of what is thought to be true considerable evidence Supported by considerable evidence Ties together related hypotheses

27 A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena theory

Laws Statement of fact A Statement of fact that concisely explains an action or group of actions e.g. Law of Gravity Accepted to be true Accepted to be true Universal Universal May be expressed as a math equation e.g. E=mc 2 28

29 Pure science is scientific research mainly for the sake of knowledge. The value of this knowledge and how it may be used is decided upon by society’s social, ethical, and moral concerns. Technology is the practical application of this research to improve human life, but can cause other different problems. Pure Science

Scientific Method Review Question (ask a question) How, What, When, Who, Which, Why, or Where? Hypothesis (form a hypothesis) An explanation for your question that can be formally tested Experiment (perform an experiment) Control Group/Independent and Dependent Variables Collect Data Make Observations Repeat your experiment Analyze the Data Conclusion (draw a conclusion) Based on facts (your data) Accepting or Rejecting your hypothesis Publish Results In a report, a scientific journal, etc. 30 Quickly Have Every Assignment Corrected Please!

Scientific Method Review 31 Quickly Have Every Assignment Corrected Please!

32 the moral principles and values held by humans ethics

33 a symbol that warns you about a danger that may exist safety symbol

MEASUREMENTS 34

Measurements SI units or metric We will be using SI units or metric system when possible --- the WHOLE world uses it except us (USA) 35

36

37