Advances in Neurotechnology

In this video segment from Greater Boston, learn how a man with severe motor disabilities can operate a computer and move a prosthetic hand by simply thinking the commands, thanks to the combined efforts of bioengineers and neuroscientists.

Accessibility features: Caption

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.

Atmospheric Pressure

Did you know that air has weight? This illustrated essay from the NOVA Web site explores conditions that affect air density and atmospheric pressure.

Blood Flow and Thermoregulation

In this interactive activity adapted from the University of Alberta, learn about the ways your body can regulate its temperature.

Blood Vessels Help Tumors Grow

In this video segment, adapted from NOVA, Dr. Judah Folkman uses the scientific method to discover how cancer cells induce the formation of new blood vessels, which in turn nourish those cancer cells.

Accessibility features: Caption

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.

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."

Accessibility features: Caption

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.

Accessibility features: Caption

Everyday Radiation

How much radiation are we exposed to every day? Find out in this video segment adapted from FRONTLINE.

Accessibility features: Caption

Facts About Radiation

This document from the FRONTLINE Web site offers examples of everyday exposure to radiation.

A Family Disease

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

Accessibility features: Caption

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.

Accessibility features: Caption

Finding Disease Genes

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

Accessibility features: Caption

Function of Fever

Fevers are a sign of infection, but they may also be part of the cure. This drawing illustrates Matthew Kluger's lizard study, which supports the notion that fever can be beneficial.

Accessibility features: Long Description

Gallery of Cells

While all cells have a great deal in common, there is no end to the variation among them. These images provide a sense of the wondrous diversity found in the world of cells.

Genetic Drift and the Founder Effect

This image of polydactyly illustrates one symptom of Ellis-van Creveld syndrome, which is commonly found in the Amish. Ellis-van Creveld is one example of the founder effect and genetic drift.

Genetics: Tour of the Basics

In this interactive activity from the University of Utah, identify different kinds of genetic traits and how they are passed on from generation to generation. View examples of simple and complex trait inheritance.

Genetic Therapy and Breast Tumors

This video segment from the Secret of Life School Video: "On the Brink: Portraits of Modern Science" explores the genetics of breast cancer.

Accessibility features: Caption

The Science Behind Appetite

This video segment, adapted from NOVA, tells the story of a ballerina battling anorexia. It explains how serotonin regulates appetite, and presents some of the health risks that accompany the eating disorder.

Accessibility features: Caption

HIV Immunity

Although repeatedly exposed to HIV, Steve Crohn's blood cells were never infected. Dr. David Ho investigates in this video segment from NOVA: "Surviving AIDS."

Accessibility features: Caption