<meta http-equiv="refresh" content="1; url=/nojavascript/">
Skip Navigation
You are reading an older version of this FlexBook® textbook: CK-12 Biology Concepts Go to the latest version.

Chapter 1: Introduction to Biology

Difficulty Level: At Grade Created by: CK-12


Is there a way to define life?

Scientifically, there is an actual definition of life. Living organisms must have certain characteristics. If they do not have these characteristics, are they living? This butterfly, like all other insects, animals, plants, and every other living organism, shares common characteristics with all life. What exactly does it mean to be alive? This chapter will answer this question. These lessons will serve as an introduction to biology, discussing basic Fundamental Concepts of Science and the Chemistry of Life.

Chapter Outline

Chapter Summary


The scientific method is the process by which biological information, like that of all other sciences, has been identified. This has resulted in a number of important biological scientific theories, including the cell theory and the theory of evolution. All life is built around carbon, and four categories of organic compounds: carbohydrates, lipids, proteins, and nucleic acids. One particular type of protein, enzymes, are biological catalysts, allowing biochemical reactions to proceed at the rate necessary to maintain life. One other molecule, water, is also essential to life, though water is not an organic compound.

Image Attributions


Difficulty Level:

At Grade



Date Created:

Feb 24, 2012

Last Modified:

Sep 11, 2015
Files can only be attached to the latest version of chapter
Please wait...
Please wait...
Image Detail
Sizes: Medium | Original

Original text