Science: Body Systems, Cells, Matter, and Experimental Design
TEAS Science spans human anatomy and physiology, life science, physical science, and scientific reasoning. Questions are largely conceptual, so understanding why a system works beats memorizing isolated facts.
Core concepts
For the human body, know the major systems and their roles - circulatory, respiratory, digestive, nervous, endocrine, immune, urinary, musculoskeletal, and reproductive - and tie each to homeostasis, the body's drive to hold internal conditions steady (for example, negative feedback lowering blood glucose after a meal). In life science, review organelles (mitochondria for energy, ribosomes for protein synthesis, nucleus for DNA), the difference between mitosis (growth, identical cells) and meiosis (gametes, halved chromosome number), the four macromolecules (carbohydrates, lipids, proteins, nucleic acids), and basic genetics with dominant and recessive alleles in Punnett squares. Physical science covers atomic structure, states of matter, physical versus chemical change, and forces and energy. Scientific reasoning asks you to identify the independent variable (what the researcher changes), the dependent variable (what is measured), constants, and the control group.
Traps
Confusing the control group with the constants, swapping independent and dependent variables, treating correlation as causation, and choosing an answer with a directional word that contradicts the data (increase vs. decrease).
Rule of thumb
Ask "what did they deliberately change, and what did they measure?" - change = independent, measurement = dependent.
Worked example: A study gives one group a supplement and another a placebo, then measures endurance. Independent variable: supplement versus placebo. Dependent variable: endurance. Control group: the placebo group, which isolates the supplement's effect.