Have you ever wondered how important gases enter and leave cells? Take an up close tour of a pore in a cell membrane. Then explore diffusion, osmosis, and active transport through this collection of interactive models.

Do you think that modern transportation limits our ability to see and/or enjoy what the first settlers saw and did?

In 1800, the United States was made up of 16 states, all east of the Appalachians, and most people lived within 50 miles of the Atlantic. Oceans and rivers were the nations' highways, providing the only viable way to travel long...

Moving materials across the cell membrane sometimes requires energy, called active transport. This tutorial covers both primary and secondary active transport with good clear animations.

[Free Registration/Login may be required to access all resource tools.] This tutorial serves as an introduction to active transport and explains how to distinguish active transport from facilitated diffusion.

This resource has information on various types of transportation and issues in Texas, and general facts.

The U.S Department of Transportation's motto is, "Safety is our top priority." To find out much more information on the Department of Transportation visit this website!

This Career Clip features Paul Davis, Group Transportation Manager with Nestle Private Fleet Nationally. His best career advice was to be positive and to be persistent. Be persistent at what you want to do, what you want to achieve and...

A German Government site with links to many excellent, up-to-date transportation sites in Germany, including information about trains, buses, cycling, automobiles, air travel, cableways, and ferries. Many of these sites are in both...

This collection uses primary sources to explore the steam engine and transportation in the nineteenth century.

[Free Registration/Login may be required to access all resource tools.] The cell membrane is semi-permeable. Sometimes molecules need the help of special transport proteins or an input of energy to help them move across it. When an input...

[Free Registration/Login may be required to access all resource tools.] During active transport, molecules move from an area of low concentration to an area of high concentration. This is the opposite of diffusion, and these molecules...

[Free Registration/Login may be required to access all resource tools.] Cells are found in all different types of environments, and these environments are constantly changing. For example, one-celled organisms, like bacteria, can be...

This report is a gateway to information on careers in the transportation field. Working conditions, earnings, job outlook, and other information is included for many transportation-related jobs.

Test your knowledge of active transport across the membrane with this quiz.

[Free Registration/Login may be required to access all resource tools.] Introduction to active transport.

[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems about reading a transportation schedule.

[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems about reading transportation schedules.

This is an eleven-question quiz pertaining to transport across a cell membrane.

Read and study the sources about the American transportation system in the late nineteenth and early twentieth centuries. As you read the four sources, think about how the development of the transportation system in the United States...

Two learning games, created by visitors to What2Learn, provide a fun way to learn how cells transport molecules.

Test your knowledge on active transport.

Use this interactive GeoStory to explore the major public transportation systems around the world.

"Transportation Changes" is a one page, nonfiction, reading passage about the history of transportation across both land and sea. It is followed by questions which require students to provide evidence from the story; it includes:...