Anatomy Quizzes

Bone Formation

Structure of skeletal muscle explained. Muscles fibres, actin, and myosin. For more information and help learning muscle structure and composition visit:

Learn the basics of bone biology, including the different elements that make up bone and how those pieces work together, in this short and visually dynamic animation.

Learn how a synapse works in the brain. From our free online course, “Fundamentals of Neuroscience”. — Subscribe to our channel:

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This animation demonstrates the behavior of a typical neuron at its resting membrane potential, and when it reaches an action potential and fires, transmitting an electrochemical signal along the axon. It shows how the various components work in concert: Dendrites, cell body, axon, sodium and potassium ions, voltage-gated ion channels, the sodium-potassium pump, and myelin sheaths. It also shows the stages of an action potential: Polarization, depolarization, and hyperpolarization. The animation was co-developed by Harvard Extension School's Office of Digital Teaching and Learning, and instructors for the courses in neurobiology and human anatomy. Learn more about Harvard Extension School: