01.20 BIO How Scientists Work (ALL)

Scientific method

A series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and drawing conclusions.

Controlled experiment

A scientific investigation in which both the control group and experimental group(s) are kept under the same variables EXCEPT for the ONE factor being studied so that the effect of that factor can be identified or determined

Variable

Any factor that can be changed.

Control group

A standard to which results can be compared

Experimental group

The group in which one variable is changed. The variable which is changed is called the independent variable. This groups' data is compared to the controls' group data

Theory

A well-tested explanation for a broad set of observations

Hypothesis

An educated guess about a possible solution to a problem that is expressed in an IF , THEN statement. i.e. If (insert independent variable), then (insert dependent variable).

Independent variable /Manipulated variable

The variable the scientist changes or manipulates so that it can be tested. Expressed after the word IF in your hypothesis. Can be referred to as the manipulated variable

Dependent variable / Responding variable

Variable that is measured and xpressed after the word THEN in your hypothesis. This is the data you collect. Think "D" for dependent = data

Controlled variables

Factors that stay the same during the experiment

Quantitative data

Can be measured, expressed in numbers that include records or time, temperature, mass, distance, and volume

Qualitative data

Data that is collected using your senses

Table

A chart to organize and record measurements that you make

Bar graph

A graph that uses thick bars to compare the frequency of data (how often something occurs) or to show comparisons among data that does not continuously change.

Line graph

A graph that shows relationships between variables that change over time