The Advantage of Sex

Why did sex evolve? The likely answers, in this essay for the Evolution Web site by science journalist Matt Ridley, may surprise you.

Bubonic Plague

In this video segment adapted from A Science Odyssey, learn about bubonic plague and how city officials in San Francisco tried to contain its spread in the early 1900s.

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Can We Slow Aging?

In this video segment adapted from NOVA scienceNOW, scientists discuss a family of genes called FOXO that can significantly extend life span in worms—and in humans.

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Chromosome Viewer

This interactive feature provides a microscopic view of the 24 Human chromosomes. Each chromosome is labeled with the names of some of the genetic conditions and traits associated with particular regions on that chromosome.

Clean Water Systems in Mexico

The push to modernize Mexico's water and sanitation systems not only saved human lives, it also spurred economic growth, as illustrated in this video segment adapted from Rx for Survival.

Dengue Virus Invades a Cell

In this visualization adapted from the University of Massachusetts Medical School, discover the role that dengue viral proteins play in a human cell as the virus prepares to replicate.

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Did Environmental Exposure Cause a Disease Cluster?

This video segment from Greater Boston examines whether environmental toxins may be to blame for a rare skin disease.

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DNA Evidence

This audio segment is a National Public Radio story on New York State's DNA profiling of criminals.

DNA on the Witness Stand

In this article, Dr. Eric Lander of the Human Genome Project comments on the use of DNA as an identification tool -- the theoretical versus the practical results.

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Double Immunity

Dr. Stephen O'Brien of the National Cancer Institute discovers a 700-year-old mutation that makes a person resistant to HIV infection. From Evolution: "Evolutionary Arms Race."

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Electrophoresis and Gel Analysis

In this animation produced by WGBH and Digizyme, Inc., see how molecules of DNA are separated using gel electrophoresis, and how this process enables scientists to compare the molecular variations of two or more DNA samples.

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The Embryo Takes Shape

This video segment from NOVA: "Life's Greatest Miracle" explores the developmental process of an embryo beginning just two weeks after fertilization.

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Epigenetics

In this video segment adapted from NOVA scienceNOW, learn how what you eat, drink, or smoke may affect the instructions your epigenomes send to your genes, and as a result, change how your DNA is expressed.

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Evolving Ideas: Why Does Evolution Matter Now?

In this video from Evolution, an exploration of multi-drug resistant tuberculosis in the Russian prison system highlights one reason it is important to understand evolution.

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A Family Disease

This video segment from NOVA: "Cracking the Code of Life" explores the implications of genetic testing for breast cancer.

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Finding Cures Is Hard

This video segment from NOVA: "Cracking the Code of Life" explains the difficulty of curing genetic diseases such as cystic fibrosis.

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Finding Disease Genes

This video segment from NOVA: "Cracking the Code of Life" explains the process of finding genes that cause disease.

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Gel Electrophoresis

This interactive activity from the Dolan DNA Learning Center illustrates the process of gel electrophoresis, in which DNA fragments are separated by size as they migrate at different rates through a gel matrix.

Genetically Engineering the Avian Flu

In this video segment adapted from NOVA scienceNOW, learn about a radical biotechnology experiment aimed at figuring out how to stop the avian flu virus.

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Genetic Engineering and Working with DNA

In this animation produced by WGBH and Digizyme, Inc., see how bacterial plasmids are engineered to clone or express genes that code for proteins such as human insulin.

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