Amphibians

This video segment from IdahoPTV's D4K points out what it means to be cold-blooded. A frog's life cycle is revealed as well as why it croaks, why it hibernates, and how it catches its prey.

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Amplitude

This interactive activity adapted from the University of Utah's ASPIRE Lab shows how a pendulum's amplitude changes as you set it swinging from different distances from its axis, and how the amplitude of a sound wave changes as you adjust the volume.

An Alaska Native Community Helps Seals

This video from First Alaskans Institute spotlights the Alaska Native community of St. Paul and its hands-on commitment to care for the land and animals on which it depends.

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Analyzing an Ecosystem

In this interactive activity adapted from the University of Alberta, identify the living and nonliving things in an ecosystem. Then look further at the living things to identify the producers, the consumers, and examples of mimicry.

An Ancient Legend Teaches Climate Change Adaptation

Today’s unsustainable use of natural resources is compared to the legend of the giant Uab, in this video adapted from the Secretariat of the Pacific Community.

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Anatomy of a Firework

There's more to a fireworks display than meets the eye. This interactive activity from the NOVA Web site looks at the technology behind each burst of light.

Anatomy of a Rover

In this interactive activity from NOVA, learn about the sophisticated scientific instruments on two identical robotic rovers that have explored Mars — Spirit and Opportunity.

Anatomy of a Tsunami

Using visual models and other graphics, this interactive activity from NOVA Online reveals details of the December 26, 2004 tsunami that collided with coasts around the Indian Ocean.

Anatomy of a Volcano

In this interactive activity from NOVA Online, explore the main features of the Nyiragongo volcano, located in the Democratic Republic of Congo, and learn what risks it poses to the 500,000 people who live in its shadow.

Ancient Farmers of the Amazon

This video segment from Evolution: "Evolutionary Arms Race" tells the story of the leafcutter ant and the fungus it farms -- an example of mutually beneficial symbiosis.

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Anglerfish

This video segment from NOVA: "Animal Imposters" shows the lightning-fast strike of the anglerfish.

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Animal and Plant Cell

Think you can tell a yam from a yak? Examine these still images of typical plant and animal cells from Biology by Kenneth R. Miller and Joseph Levine. What similarities and differences can you find?

Animal Babies

This interactive slide show illustrates the variety of animal babies that exist on earth -- some completely independent and others deeply reliant on parental care.

Animal Body Plans: Homeobox Genes

The homeobox genes that define the basic body plan of mice and fruit flies are illustrated in this graphic from The Human Evolution Coloring Book by Adrienne Zihlman. The accompanying article describes how these genes act as "molecular architects" in all animal species.

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Animal Chefs

Ever wonder how to tempt the taste buds of a 400-pound mola mola? In this video from QUEST produced by KQED, learn how the chefs at the Monterey Bay Aquarium prepare meals to feed thousands of species.

Animal Classification Game

Learn about classes of animals and test your ability to identify animals as mammals, birds, reptiles and more in this interactive activity adapted from Sheppard Software.

Animal Cloning 101

Learn about clones and explore the methods scientists use to create clones in the lab in this interactive activity from the Dolan DNA Learning Center.

Animal Coverings

It takes a thick skin to withstand the hardships that life has to offer. This collection of images shows a variety of animals, each with a slightly different type of protective covering.

Animal Defenses

In nature, survival is the name of the game. This video segment explores the world of animal defense and shows that predators don't always have the upper hand.

Accessibility features: Audio Description, Caption

Animal Families

How long does a baby elephant stay with her mother? What do you call a baby goat? Young children learn some interesting facts about the lives of baby animals in this original video from KET.