Aldol and retro-aldol are two important classes of chemical reactions, occasionally encountered in biochemistry too.

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

A complete resource including a biography, chronology, examples of Wallace's published work, quotes, and interviews.

Visit this site to find out what covalent compounds are, how covalent bonding is different from ionic bonding, how the properties of covalent compounds differ from ionic compounds, and how to name covalent compounds. There is also a link to some practice problems on naming covalent compounds.

In this lesson, students will become familiar with glaciers, how they form, move, and shape the land.

Learn about allele frequencies in populations and how they differ from genotype frequencies. [7:27]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Understand how a gene is a stretch of DNA on a chromosome. Find out about alleles in their role as versions sequence variants of a gene. [8:18]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Learn about the gene as a stretch of DNA on a chromosome. Also find out about alleles as versions or sequence variants of a gene. [8:17]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Students are asked to explain what needs to be considered if alternative energy sources are to be used. [0:32]

This video segment from the Secret of Life School Video: "Genetic Medicine: Tinkering with Our Genes" explores the potential for gene therapy to cure diseases like Alzheimer's.

This teacher website provides a comprehensive lesson unit on the structure of Earth's atmosphere and how it sustains and impacts life on Earth and its ecosystems. Includes labeled diagrams, student worksheets, a slideshow, flashcards, and links to an interactive lab, videos, and resource sites.

Enhance your health, science, and environmental studies curriculum with this video which features a landfill in South Jersey and examines the state of food waste in America today. Then, use the accompanying lesson plan, "Making Mountains Out of Landfills: Telling a Visual Story of Waste," to prepare students to visually track and document different kinds of trash in their community. English and Spanish versions with closed captions. [5:26]

Engaging hands on science lessons for grades 2-6 on the three states of matter.

Promotes the benefits of maintaining a sustainable future for American forests. Outlines initiative to fight urban sprawl and its negative effects on the environment.

The American Geological Institute has done an excellent job of defining and explaining evolution in this online booklet. Darwin, fossils, natural selection, and change over time are some of the concepts that are covered. Make sure to see the examples of evolution at the end. The booklet can also be downloaded in PDF format.

Resource provides information about nuclear energy. Read about current events, radiation doses, radiation emergency kits, and more. Also contains a helpful glossary of radiation and nuclear energy terms. Parts of the site are for members only.

This site is the homepage of the American Society of Mechanical Engineers (ASME).

After explaining the difference between cleavage and fracture, this resource discusses various types of cleavage and their importance in identifying minerals.

Streak is the color of the powder of a mineral. This page discusses the importance of streak when identifying minerals.

Anaphylactic shock also known as anaphylaxis anaphylactic shock is an allergic reaction severe enough to cause shock. Description, diagnosis, and treatment are examined in this video.

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Explains the basics of atomic structure, from simple definitions to information about quantum theory. Accurate and helpful basics whether or not you need the more advanced information.