Blood Circulation: Heart, Loops, and Oxygen
Trace pulmonary and systemic loops, oxygen saturation, and how activity changes heart rate and flow.
Evolution and Natural Selection
Study variation, natural selection, and inheritance through trait changes in a population.
All Simulations
Breathing and Gas Exchange: How the Body Gets Oxygen
Follow air to the alveoli, track O₂/CO₂ exchange with blood, and compare rest vs load breathing.
Digestion and Enzymes: How Food Turns Into Nutrients
Show the food pathway, carb/protein/fat breakdown, and small-intestine absorption with pH effects.