Learn how cells use checkpoints to regulate the cell cycle. This article provides an overview of cell cycle control, outlining the factors that influence a cell's decision to pause or progress at each checkpoint.

Resource explains apoptosis (programmed cell death) and how it is different from necrosis (cell death due to injury).

This interesting site provides videos and photos of cells going through the process of cell division. Observe Zebrafish development and Sea urchin embryo cell division in video format.

Often referred to as the powerhouses of the cell, mitochondria provide the energy that powers nearly every cellular process. This essay by university lecturer John Ross describes in detail the structures and functions of these amazing...

Describes the structure and coding of DNA, how it replicates, and the role it plays at the cellular level. Looks at past and current research on DNA, and applications of this research. (Published: September 25, 2010)

[Free Registration/Login may be required to access all resource tools.] This activity explores the significance and functions of carbon and explains why carbon is essential to life on Earth. Students will investigate and explain cellular...

Article explores the life cycle of a cell and delves into the phases of the cell cycle.

This article looks at a few of the most important core cell cycle regulators: proteins called cyclins, enzymes called Cdks, and an enzyme complex called the APC/C.

A very brief explanation of the structure and function of this organelle.

Description of organelles. Links will take you to a glossary with pictures for many of the definitions. Ends with a quiz linked to answers.

Choose a cell type and go inside to see how its signals travel. The response depends on the type of cell the signal reaches. Cell types include photoreceptor, muscle cell, fibroblast, leaf parenchyma, and cancer.

[Free Registration/Login may be required to access all resource tools.] A variety of learning opportunuties about levels of organization in the human body. Includes videos, activities, discussion questions, and quizzes.

The materials on this page were prepared by a high school teacher for a Biology class. This section supports a unit on cell energy and includes course readings, lab notes, PowerPoints and diagrams.

NADH and NADPH are enzymes involved in cellular processes. Explains how NADH participates in catabolic reactions where energy is released and NADPH is involved in anabolic reactions where energy is consumed. Their functions and chemical...

This site lets students practice vocabulary words related to cell organelles. The same vocabulary words are presented in one of four different games for students.

Learn about the many ways cell communication can be disrupted, and how this problem sometimes results in disease.

[Free Registration/Login may be required to access all resource tools.] All cells have a barrier around them that separates them from the environment and from other cells. This barrier is called the plasma membrane, or cell membrane....