Download Scientific Method

Scientific Method
Scientific Method
•Steps to solve a
scientific problem
or answer a
question
•6 Steps!
1. Observing
• Taking note of a problem
• Ex. 1976 deadly pathogen (Ebola) appeared in the
Congo
• Doctors observed symptoms and and locations to
determine cause
2. Asking a Question
• All investigations begin with questions
• Determines what needs to be investigated
further
• Ex. How was the disease transmitted? What is
the disease causing agent?
3. Collecting Data (what is already known)
• Longest phase of scientific investigation
• Data – all information gathered to answer
questions
• 4 Parts:
1. Observing – recording unusual events that
raise questions
2. Measuring – quantitative data (numbers)
3. Sampling – using a sample to represent a
whole population (must be large and
random)
4. Organize Data – using charts, tables, graphs,
etc.
4. Hypothesizing
• Hypothesis – suggested explanation for
observation/question
• Statement is testable
• Can be supported or rejected never proven
• Prediction – states the results of the hypothesis
• “If…then...” statement
• Ex. If the virus were the true disease causing agent,
then introducing the virus into healthy tissue would
cause cell death.
5. Experimenting
• Experiment – testing a hypothesis by gathering data in controlled
conditions
• Aspects:
oControl group – group not subjected to what is being tested
oExperimental group – group subjected to what is being tested
oIndependent variable – one thing you do different between the
two groups
oDependent variable – measured results of the experiment
oData analysis! Is it statistically significant?
VI
DV
How does _______________ affect _______________?
5. Experimenting
Example:
Group A kidney cells exposed to infected blood. Group B
kidney cells not exposed to infected blood. Scientists observed
cells over many days. Group A kidney cells died
What is the independent Variable?
What is the dependent variable?
What is the control group?
What is the experimental group?
6. Drawing Conclusions
• Modeling, inferring, and forming a theory
• Modeling – explanation supported by data
• Inferring – conclusion made on data
• Forming a theory – comprehensive statement of what
is thought to be true and is backed up with lots of
supporting data
• Ex. Ebola fever is a virus that was transmitted with
close contact with infected victim
Report Findings!
•Scientific Journals
•Presentations
•Books
•Media