Different gaits employed by animals and how the nervous system is able to switch between them.
Problems associated with adherence to antiviral drugs, and a student activity that mimics adherence to a multi-drug regimen.
A brief discussion of what makes a virus a retrovirus, and how they differ from other types of viruses.
An overview of the immune system, concentrating on the roles played by B and T lymphocytes, and the antigen-presentation system.
An exploration of current and future therapies.
An overview and comparison of different regenerative capabilities in many different organisms.
Learn about how gene switches can control expression of genes in different tissues.
Learn about artificial and natural selection.
Learn about the different ways scientists are able to detect when genes are being expressed in various tissues.
This slide show explores some of the ways the body processes fat, including digestion, transport, conversion, and energy extraction.
This slide show delves into the various molecular shapes that fat can take.
There is no way to directly measure how much fat a living person has. Learn about the various methods used by researchers and fitness advisors to estimate a person’s body fat.
Learn about the structure and function of this fascinating cellular machine.
Learn about what p53 does, and how interfering with its function can lead to cancer.
All living humans originated from populations of ancestors who migrated out of Africa less than 100,000 years ago. Learn how scientists have used genetic markers to trace the migration routes and origins of modern human populations.
DNA microarrays, or gene chips, are an important new technology for genomic research. Learn how researchers use computing to analyze and interpret the huge datasets generated by microarray experiments.
Small molecules are chemicals that can interact with proteins to affect their functions. Learn about the structure and biological functions of various small molecules like sugar and caffeine.
How both gene chips and microarray slides are created.
Learn why verifying a person's gender may be harder than you think.
Answer the questions in this online quiz to test your knowledge of what determines the sex of a human, a fruit fly, and a snapping turtle.
This survey, developed by Horne and Ostberg, will let you determine if you are a morning or an evening person.
Take this quiz to see how well you understand some of the topics covered in the 1999 Holiday Lectures on infectious disease.
This mini-lesson covers the research on telomeres that has happened since the 1995 Holiday Lectures.
RNA is an information molecule that can also function as an enzyme. Learn about the many different forms that RNA can take.
RNA interference is an exciting new research tool for shutting down genes. It could also yield new medical treatments.