Biology: Chapter 1, The Science of Biology

Microscope

devices that produce magnified images of structures that are too small to see with the unaided eye.

Population

group of organisms of one type that live in the same area

Data

information gathered from observations is called evidence, or data.

Observation

involves using one or more of the senses -- sight, hearing, touch, smell, and sometimes taste -- to gather information.

Inference

is a logical interpretation based on prior knowledge and experience.

Things to remember about theories

No theory is considered absolute truth. New evidence may result in theory revisions or replacement with better explanations.

Cell

a collection of living matter enclosed by a barrier that separates the cell from its surroundings. Cells are the smallest units of an organism that can be considered alive.

Hypothesis

a possible explanation for a set of observations or an answer to a scientific question.

Community

populations that live together in a defined area.

Groups of cells

similar specialized cells form tissues, organs, and organ systems

Cells

smallest functional unit of life

Ecosystem

Community and its nonliving surroundings.

Short definition of science

An organized way of using evidence to learn about the natural world. The word science also refers to the body of knowledge that scientists have built up after years of using this process.

Theory

Applies to a well-tested explanation that unifies a broad range of observations. A theory enables scientists to make accurate predictions about new situations.

Organism

Individual living thing

Qualitative observations

Involve characteristics that cannot be easily measured or counted, such as color or texture.

Quantitative observations

Involves numbers, for example, counting or measuring objects.

Manipulated variable (Independent)

The variable that is deliberately changed is called the manipulated or independent variable.

Responding variable (Dependent)

The variable that is observed and that changes in response to the manipulated variable is called the responding or dependent variable.

Controlled experiment

Whenever possible, a hypothesis should be tested by an experiment in which only one variable is changed at a time. All other variables should be kept unchanged, or controlled.

Biosphere

the part of Earth that contains all ecosystems.

Biology

the science that seeks to understand the living world.