Explains what the Uncertainty Principle developed by Werner Heisenberg is and its applications in electron movement and in quantum mechanics. [9:38]

Discusses the concept of heritability and how this applies to human intelligence. [6:40]

Explains how we measure the mass of an atom. [8:33]

This video describes the structure and function of astrocytes. [7:25]

How does ATP provide energy for biosynthesis reactions? Use an understanding of Gibbs Free Energy to understand how ATP is coupled to energy-requiring processes. [7:41]

Offers an explanation of Gibbs free energy using an analogy. [9:19]

A major branch of psychology is Humanism. Learn what the humanistic theorists have to say about how we develop our personality. [6:06]

Watch a demonstration of one way to approach questions in the LSAT that ask you to apply information presented in the passage to new contexts. The example in this case analyzes the ownership of intellectual property. [3:49]

An exploration of aromatic stability as it relates to benzene. [5:59]

David works through an apostrophe use question from the Praxis Core Writing test. [3:23]

Looks at some differences between the left and right hemispheres of the brain. [4:37]

Explains what altruistic behavior looks like and the benefits it offers to society and to individuals. [3:55]

Discusses the life and work of Solomon Asch and the role of group behavior on an individual's behavior. [9:56]

Discusses enzyme kinetics and the role enzymes play in reactions. [4:44]

Explains what aromatic heterocycles are. [11:49]

Explains what DNA hybridization and a microarray are and how this biotechnology is used. [8:57]

An advanced problem from an IIT JEE exam on algebraic manipulation. IIT JEE stands for: Indian Institute of Technology Joint Entrance Examination. [13:11]

This video lesson [14:00] looks at a problem on differentiability and boundedness. IIT JEE stands for: Indian Institute of Technology Joint Entrance Examination.

Sal Khan works through an algebraic word problem question from the Praxis Core Math test. [4:19]

Learn about driving forces of evolution other than natural selection. Group selection and artificial selection are just a few of these forms of 'Alternative Selection.' [4:34]

Sal Khan works through a question on algebraic properties from the Praxis Core Math test. [5:45]

Watch Sal work through a basic Linear equations word problem.

Mr. Andersen describes the two portions of the AP Biology Test. Tips for answering multiple choice and free response questions are included. Sample questions from old AP tests are also included. [14:47]