Interactive Biology Visualizations
All 137 animations →The 32 our readers open most. Press play and watch a part of the body work — then break it on purpose and see what changes, with sound and live readouts in real clinical units.
Menstrual Cycle
Sweat & Cooling
Magnesium & ATP
DNA → Protein
Meiosis
Blood pH & Acid–Base
Vitamin D
Thirst, ADH & Water
Vitamin C & Collagen
Mitochondria & ATP
Brown Fat & Heat
Calcium & PTH
Antibiotic Resistance
Cyclospora Outbreak
The Baroreflex
Free Radicals
Vitamin B12
Apoptosis
Vitamin K & Warfarin
Red Cells & EPO
Anaphylaxis & EpiPen
Autophagy & Fasting
Asthma & Inhalers
Eye Focusing
Inside the Beta Cell
Lung Surfactant
Biofilms
Kidney Nephron
Complement System
CRISPR
Clot Busting
Fertilization
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Plain-language, referenced articles across every area of health — conditions, nutrition, and the lab tests that measure them.