Human Body
How Does the Eye See Colors?
Retinal cone cells respond to overlapping wavelength ranges and the brain compares their signals to construct color perception in context.
Human Body
Explore sleep, memory, the heart, vision, and human biology.
Human Body
Why Does Our Heart Keep Beating?
Pacemaker cells in the sinoatrial node spontaneously produce electrical impulses that coordinate heart-muscle contractions and blood flow.
Human Body
How Does the Human Brain Store Memories?
Memory is distributed across neural networks; changing connections encode information while the hippocampus helps organize many new declarative memories.
Human Body
Why Do Humans Need Sleep?
Sleep supports memory, learning, immune regulation, metabolism, emotional control, and tissue maintenance through repeating non-REM and REM stages.