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Learn about the components of blood and their functions in the circulatory system.

Adaptive immunity is a specific immune response that targets and remembers pathogens for future defense.

Detailed overview of the plasma membrane and cytoplasm in cells.

Learn about the membrane potential and how it is generated in neurons.

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Explanation of prokaryotic cells, including structure, function, and examples.

Learn about prokaryote metabolism and nutrition on Khan Academy.

Introduction to vector components and their uses in mathematics and physics.