Biology 9 Chapter 1

Science

An organized way of gathering and analyzing evidence about the natural world

Observation

The act of noticing and describing events or processes in a careful, orderly way

Inference

Logical conclusions based of what is already known

Hypothesis

A scientific explanation for a set of observations that can be tested in ways that support or reject it

Data

Quantitative: Data is/are numbers obtained by counting or measuring

Qualitative: Cata is/are descriptive and involve characteristics that cannot be counted

Theory

A tested and reasoned explanation for why something happens, backed by evidence

DNA

The molecule that carries the genetic code for all organisms

Stimulus

A signal or change in the environment

Sexual Reproduction

2 parents combine genetic material to create one offspring. They are genetically unique

Asexual Reproduction

A single parent creates genetically identical offspring

Homeostasis

All living organisms use energy to keep conditions inside their cells within certain limits

Metabolism

All the chemical reactions through which an organism builds up or breaks down materials

Biosphere

The global zone on Earth where all life takes place, including all plants, animals, and microorganisms

Controlled Experiment

An experiment in which only 1 variable is changed

Independent Variable

The variable that is deliberately changed by the experimenter

Dependent Variable

The variable that changes in response to the independent variable

Control Group

Exposed to the same conditions as the experimental groups except for one variable; necessary because it serves as a standard for comparison

Experimental Group

Receives the specific treatment or change being tested