Carrier proteins and channel proteins are both involved in cell transport across the plasma membrane. Their functions, similarities, and differences are described in this resource. Includes examples for active, facilitated, and passive...

Explanation of complex and dynamic cell structures that are selective in regards to what is allowed to enter and exit cells.

[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 site has information on how facilitated diffusion of ions takes place through proteins, or assemblies of proteins, embedded in the plasma membrane. Includes a helpful diagram.

Explanation of cell membranes and the way selective materials may move through them.

Explanation of the different ways the chemicals or medicines may enter the body through cell membranes.

[Free Registration/Login may be required to access all resource tools.] Describes four parts all cells have in common.

[Free Registration/Login may be required to access all resource tools.] Covers the common shapes and features of prokaryotic cells.

Through full-color images and concise information, learn about the origin of cells. Discover some of the notable studies surrounding the history of life on Earth.

This resource is a cellular biology course site with clickable list that provides electron micrographs of various cell organelles and the like.

Students will be able to identify two ways that molecules and ions cross the plasma membrane.

Provides a labeled diagram of a plant cell and descriptions of the characteristics and functions of many of its organelles.

This module focuses on cell structure and how the organelles function together to form the smallest unit of life. The cell theory is also discussed along with the basics features of the cell. Site also includes an interactive practice...

[Free Registration/Login may be required to access all resource tools.] Online activity summarizes the cell theory, describes four parts all cells have in common, and the importance of the work of Robert Hooke and Anton van Leeuwenhoek.

An in-depth discussion of the different parts of eukaryotic and prokaryotic cells as well as a thorough explanation of organelles within the cell. The text is better suited to high school and middle school. However, there is a picture of...

This tutorial compares prokaryotic and eukaryotic cellular organization and contrasts cells with viruses. Includes a practice quiz to test your knowledge.

Wikipedia offers brief but accurate information on cytoplasm, the matter contained within the plasma membrane of a cell.

This site from the Wikipedia Encyclopedia describes the process of exocytosis and what is accomplished by the process. Throughout this brief article, links are provided for additional information on the subject.