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Introduction to Life ScienceLiving ThingsCell Processes and EnergyGenetics: The Science of HeredityModern GeneticsChanges Over TimeViruses, Bacteria, Protists, and FungiPlantsSponges, Cnidarians, and WormsMollusks, Arthropodsand EchinodermsFishes, Amphibians, and ReptilesBirds and MammalsAnimal BehaviorBones, Muscles, and SkinFood and DigestionCirculationRespiration and ExcretionFighting DiseaseThe Nervous SystemThe Endocrine Systemand ReproductionPopulations and CommunitiesEcosystems and BiomesLiving Resources