Foundations of Physiology

Foundations of Physiology on STEM Calculators is a practical set of human physiology calculators that build the quantitative basics used throughout physiology and health science. It covers essential tools for physiology unit conversions, percentage change and rate calculations, and core “numbers-first” thinking needed for labs, homework, and real problem solving.

This chapter includes calculators for body fluid compartments (total body water, intracellular fluid, extracellular fluid, and common subdivisions), concentration and dilution (C = amount/volume and C1V1 = C2V2), and introductory homeostasis modeling with set point, deviation, correction strength, and negative feedback updates. The difficulty level is beginner to intermediate, with clear workflows that also help advanced users quickly verify calculations and avoid unit or sign mistakes.

Students and self-learners can use these physiology tools to practice and check answers step by step, teachers can validate examples and build accurate classroom demonstrations, and advanced users can speed-check quantitative assumptions used in physiology and biomed contexts. Use this page to master foundational physiology math, understand how changes in values translate into biological meaning, and build confidence before moving into more complex system-based physiology calculators.