Unit 0: Methods of Science

Bar Graph

a graph that uses vertical or horizontal bars to show comparisons among two or more items

Biology

the scientific study of life

Box and Whisker Plot

a diagram that summarizes data using the median, the upper and lower quartiles, and the extreme values (outliers).

Cell

smallest unit of life

CER

Claim, Evidence, Reasoning

Chi-Square

a common statistic used to analyze nominal and ordinal data to find differences between groups

Control Group

in an experiment, the group not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment

Controlled Experiment

experiment in which only one variable is changed

Controlled Variables/Constants

the experimental element which is constant and unchanged throughout the course of the investigation.

Critical Value

the dividing point between the region where the null hypothesis is rejected and the region where it is not rejected.

Data Table

an arrangement of data in which each row represents a case and each column represents a variable

Degrees of Freedom

The number of individual scores that can vary without changing the sample mean. Statistically written as 'N-1' where N represents the number of subjects.

Dependent Variable

the measurable effect, outcome, or response in which the research is interested.

DNA

deoxyribonucleic acid, a self-replicating material present in nearly all living organisms as the main constituent of chromosomes. It is the carrier of genetic information.

Error Bars

on bar or line graphs, they indicate the amount of variability around a mean; often reflect standard deviations or confidence intervals

Evolution

the gradual change in a species over time

Experimental Group

the group in an experiment that receives the variable being tested

Hypothesis

a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.

Alternative Hypothesis

the hypothesis that states there is a difference between two or more sets of data.

Independent Variable

variable that is manipulated

Law

a descriptive statement or equation that reliably predicts events under certain conditions

Line Graph

a graph that uses one or more lines to show changes in statistics over time or space

Line of Best Fit

a smooth line that reflects the general pattern in a graph

Mean

average

Negative Control

group with no response expected

Null Hypothesis

the hypothesis that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error.

P-Value

the probability of results of the experiment being attributed to chance

Positive Control

treatment with known response

Product

a substance that forms in a chemical reaction

Qualitative Data

descriptive data

Quantitative Data

numerical data

Rate

a measure, quantity, or frequency, typically one measured against some other quantity or measure.

Reactant

a substance that takes part in and undergoes change during a reaction.

Scatter Plot

a graph with points plotted to show a possible relationship between two sets of data

Science

organized way of gathering and analyzing evidence about the natural world

Standard Deviation

a measure of variability that describes an average distance of every score from the mean

Standard Error of the Mean

the standard deviation of a sampling distribution

Statistical Significance

a statistical statement of how likely it is that an obtained result occurred by chance

Statistics

the collection and classification of data that are in the form of numbers

Theory

a hypothesis that has been tested with a significant amount of data

Trial

each repetition or observation of an experiment

Variable

a factor that can change in an experiment

X-Axis

the horizontal line on a graph

Y-Axis

the vertical line on a graph