Blood Circulation: Heart, Loops, and Oxygen
Trace pulmonary and systemic loops, oxygen saturation, and how activity changes heart rate and flow.
Selective Animal Breeding: Create a New Breed
Understand how parent selection and generation-by-generation selection produce a new animal breed.
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.