When two or more atoms combine they give rise to a molecule. A molecule can be made up of many atoms of the same element. There are 112 elements known to man, so can you imagine the different permutations and combinations of molecules...

George Zaidan and Charles Morton shape our image of molecules. [3:47]

In this activity, students construct models of molecules using marshmallows and gum drops.

Great site which gives the chemical structure and reactions involved in aspirin production. If you have the CHIME plug-in then it links to a better site with a 3-D model you can manipulate. OR BETTER YET, if your browser has Java, then...

A complete lesson on compounds, from introductory material in the beginning to a practice exam at the end. This lesson covers bonding, ionic compounds, molecular compounds, naming compounds, structural formulas, polyatomic ions, and much...

Online biology textbook discussing the chemical nature of water, and the importance of its molecular structure to life. Also discusses at length the organic molecules nucleic acids, proteins, lipids, and carbohydrates.

An animated tutorial showing how each chromosome consists of one continuous thread-like molecule of DNA coiled tightly around proteins. [1:42]

In this online biology textbook, learn about atoms and molecules as they relate to life. Find out about topics such as electrons and energy, chemical bonding, and chemical reactions.

Practice questions over regulating electron carrier molecules.

Discover what you know about the nature of molecules by taking this post test.

An explanation of why carbohydrates are important nutrients for the human body. Chemical formulas and structures are used to demonstrate simple and complex carbohydrates.

An explanation of the importance of fats and proteins in the human diet. Examples of chemical structures of various fats and proteins are used.

This general tutorial begins with an explanation of the polarity of the water molecule and the effects this polarity has on the properties of water. Goes on to introduce organic molecules and has a thourough tutorial on the third page.

[Free Registration/Login may be required to access all resource tools.] Students investigate compounds, and learn the ways in which molecules are named.

See how temperature changes affect dissolving and the molecular bonds in a water molecule.

This section in the online textbook describes how to tell if a molecule is polar or non polar. Detailed steps and examples are good references. Also find links to presentations and chapter maps for other chemistry topics.

Read about carbohydrates, which make up one of the three "Major classes of macronutrients that are essential to living organisms." In addition to defining several terms, including carbohydrate, simple sugars, complex carbohydrates,...

Find out about the process of transcription, where the DNA sequence of a gene is transcribed to make an RNA molecule.

Learn how basic elements form molecules to support life.

This simulation can be used to study molecule movement across a semipermeable membrane.

A great page for all around biochemistry and background information. Includes the molecular structure and most of the information relevant to its role in living cells.

In this learning module from The Concord Consortium, students will investigate how polar and nonpolar regions in big molecules interact to result in certain shapes and properties for those molecules.

In this interactive activity from NOVA, learn about the molecular structure of steroids. See the intermediate molecules that are part of the pathway for synthesizing cortisone from diosgenin.

This site helps students construct a model of the arrangement of water molecules when present as solid, liquid or gas. Includes background information, lesson plans, links to standards and assessment ideas.