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This collection is being developed for the revised MCAT® exam that will first be administered in spring 2015. Videos will be added to the collection through fall 2014. All content in this collection has been created under the direction of the Khan Academy and has been reviewed under the direction of the Association of American Medical Colleges (AAMC). All materials are categorized according to the pre-health competencies tested by the MCAT²⁰¹⁵ exam; however, the content in this collection is not intended to prescribe a program of study for the MCAT²⁰¹⁵ exam. The content is also included in the Pre-health Collection within MedEdPORTAL’s iCollaborative sponsored by the AAMC: www.mededportal.org/pre-health *MCAT® is a program of the AAMC and related trademarks owned by the Association include Medical College Admission Test, MCAT, and MCAT²⁰¹⁵. For more information about the MCAT exam visit : www.aamc.org/mcat2015
Community Questions

Biological sciences practice passage questions

Physical sciences practice passage questions

Social sciences practice passage questions


Foundational Concept 1: Biomolecules have unique properties that determine how they contribute to the structure and function of cells, and how they participate in the processes necessary to maintain life.


Foundational Concept 2: Highly-organized assemblies of molecules, cells, and organs interact to carry out the functions of living organisms

Organ systems

Foundational Concept 3: Complex systems of tissues and organs sense the internal and external environments of multicellular organisms, and through integrated functioning, maintain a stable internal environment within an ever-changing external environment.

Physical processes

Foundational Concept 4: Complex living organisms transport materials, sense their environment, process signals, and respond to changes using processes that can be understood in terms of physical principles.

Chemical processes

Foundational Concept 5: The principles that govern chemical interactions and reactions form the basis for a broader understanding of the molecular dynamics of living systems.

Processing the environment

Foundational Concept 6: Biological, psychological, and socio-cultural factors influence the ways that individuals perceive, think about, and react to the world.


Foundational Concept 7: Biological, psychological, and socio-cultural factors influence behavior and behavior change.

Individuals and society

Foundational Concept 8: Psychological, socio-cultural, and biological factors influence the way we think about ourselves and others.

Society and culture

Foundational Concept 9: Cultural and social differences influence well-being.
Physical processes
Foundational Concept 4: Complex living organisms transport materials, sense their environment, process signals, and respond to changes using processes that can be understood in terms of physical principles.
All content in “Physical processes”

Vectors and scalars

4A: Find out what makes vectors different from scalars! Find out how to break vectors into components, and go over the different ways to represent vectors. By Sal.

Normal forces

4A: Learn about the normal force, and try some examples that demonstrate how the normal force is affected by the motion of an elevator, as well as how the normal force affects friction. By Sal.

Work and energy

4A: Learn about the concepts of work, mechanical advantage, and power. After understanding the principle of conservation of energy, you can apply it to different types of energy including kinetic energy, gravitational potential energy, and spring potential energy. Finally, learn about the conservative force as well as how to find mechanical advantage. By Sal and David SantoPietro.

Kinetic molecular theory of gases

4A: Gases are composed of atoms and molecules. In these videos you'll learn about how molecular behavior determines the pressure and temperature of a gas. You'll also learn about Boltzmann's constant, the first law of thermodynamics, and the heat capacity of a gas.

Fluids at rest

4B: Learn the physics behind fluids at rest. Some of the ideas explored are density, pressure, Pascal's principle, Archimedes' principle, buoyant forces, and specific gravity. By Sal.

Gas phase

4B: Let's learn about gas phase chemistry! Discover the history and application of the ideal gas law. We'll walk through topics like temperature, STP, partial pressure, and the difference between real gases and their ideal counterparts. By Ryan Patton.


4C: In these videos you'll learn what electric charge is and how it interacts with other electric charges. You'll learn about the electric force, electric fields, electric potential, and electric potential energy.

Thin lenses

4D: In these videos you'll learn how to draw ray tracings to find images created by thin lenses. You'll also learn how use the thin lens formula and magnification equation to calculate image distances and heights. The human eye, lens power, and aberration will also be discussed.

Spherical mirrors

4D: These videos go over the images formed by curved mirrors. It will be explained what a real and virtual image is and how to draw ray tracings to determine the location and size of the image formed. By David Santo Pietro.

Reflection and refraction

4D: These videos describe the reflection and refraction of light rays. Topics discussed will include the different types of reflection, how to determine which way light bends, Snell's law, total internal reflection, and dispersion. By David Santo Pietro and Sal Khan.

Light and electromagnetic radiation

4D: These videos will explain the model of light and its wave-like and particle-like properties including polarization, interference, and the photon model. You'll learn how light rays can interfere in double slit, single slit, and diffraction gratings. Thin film interference will also be explained.

Redox reactions

4E: Discover how to assign oxidation states/numbers in redox reactions, then go on to balance redox reactions! By Jay.