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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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.

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Cell Differentiation

In this video segment from The Secret of Life school video, "Sex and the Single Gene" follow as a single fertilized egg cell divides, differentiates, and assembles into the tissues and organs of a new organism.

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Cell Division

In this interactive activity adapted from the Exploratorium, explore the step-by-step process by which an animal cell divides to make more cells.

Cell Transcription and Translation

In this interactive activity adapted from the University of Nebraska, learn how and where transcription and translation occur within a cell and observe both processes in detail.

Chemical Risks to a Fetus

Learn about the risks environmental contaminants pose for a developing fetus, in this video adapted from Contaminated Without Consent.

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The Effects of Pesticides on Children

Follow anthropologist Elizabeth Guillette as she studies the effects of pesticides on children in a farming community in Mexico, in this video segment adapted from Playing with Poison.

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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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Endocrine Disruptor Hypothesis

Scientists discuss whether or not endocrine disrupting chemicals, which may cause birth defects and other health concerns, should be controlled in the absence of conclusive proof, in this video segment adapted from FRONTLINE: "Fooling with Nature."

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Evolution of the Eye

Zoologist Dan-Erik Nilsson demonstrates how the complex human eye could have evolved from simple light-sensitive cells. From Evolution: "Darwin's Dangerous Idea."

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Gene Control

The development of creatures that appear to have nothing in common is directed by a surprisingly small number of genes. In this video segment, learn about the power of master control genes. Footage from The Secret of Life: "Birth, Sex & Death."

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Genetic Tool Kit

The shared set of genes for body segments, possessed by all animals, are discussed in this video segment from Evolution: "Great Transformations."

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On Human Cloning

Three cloning experts share their opinions in these interviews from the NOVA "18 Ways to Make a Baby." Web site.

Plants-in-Motion

While we tend to think of plants as stationary, they are in constant, though very slow motion, as they respond to environmental factors. Watch plants move in time-lapse videos in this interactive activity adapted from Indiana University.

Preimplantation Genetic Diagnosis

This video segment from NOVA: "18 Ways to Make a Baby" describes a technique used to determine the health of a developing embryo.

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RNAi Discovered

In this video segment adapted from NOVA scienceNOW, learn how RNAi, a mechanism that has evolved in cells to prevent viral infection, was discovered and how it works.

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Stem Cells: Seeds of Hope?

This video explores the basic scientific and ethical questions surrounding the use of stem cells in medical research.

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