Scientific Principles & Biological Systems Revision Sheet

1. 📌 Essentials

• The scientific method involves hypothesis, experimentation, data analysis and conclusion.
• SI units: meter (m), kilogram (kg), second (s), mole (mol), liter (L).
• Newton's: inertia, $F=ma$, action-reaction.
• Force measured in Newtons (N); work in Joules (J); power in Watts (W).
• Pressure: $P=F/A$; measured in Pascals (Pa).
• pH scale: logarithmic, ranges 0-14, indicates acidity or alkalinity.
• Water's polarity enables hydrogen bonding, high specific heat.
• Enzymes: biological catalysts lowering activation energy.
• Fluid mechanics: pressure, buoyancy, flow dynamics.
• Atomic structure: protons, neutrons, electrons define element properties.
• Chemical bonds: ionic and covalent influence molecule stability.
• Thermodynamics: energy transfer, entropy, vital in biological processes.

2. 🧩 Key Structures & Components

• Atoms — basic units of matter, composed of protons, neutrons, electrons.
• Molecules — water, carbohydrates, lipids, proteins.
• Chemical bonds — ionic (transfer of electrons), covalent (sharing electrons).
• Enzymes — proteins that catalyze biochemical reactions.
• Fluid systems — blood, airways, governed by pressure and flow.
• pH scale — measures hydrogen ion concentration.
• Energy carriers — ATP, NADH in cellular processes.
• Thermodynamic systems — biological energy transfer and heat exchange.

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