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.

3. 🔬 Functions, Mechanisms & Relationships

• Atomic structure determines element properties and reactivity.
• Chemical bonds influence molecule stability and biological activity.
• Enzymes catalyze reactions by lowering activation energy.
• Fluid flow depends on pressure gradients and viscosity.
• Biological systems maintain homeostasis via feedback mechanisms.
• Energy transfer in cells involves ATP hydrolysis and electron transport.
• pH affects enzyme activity and biochemical reactions.
• Water's polarity facilitates solvation and biochemical interactions.

4. 📊 Comparative Table

5. 🗂️ Hierarchical Diagram (ASCII)

Biological System
 ├─ Atomic Level
 │    ├─ Proton
 │    ├─ Neutron
 │    └─ Electron
 ├─ Molecular Level
 │    ├─ Water
 │    ├─ Carbohydrates
 │    ├─ Lipids
 │    └─ Proteins
 ├─ Cellular Level
 │    ├─ Enzymes
 │    ├─ DNA
 │    └─ Organelles
 └─ System Level
      ├─ Circulatory System
      ├─ Respiratory System
      └─ Nervous System

6. ⚠️ High-Yield Pitfalls & Confusions

• Confusing ionic and covalent bonds; ionic involves electron transfer.
• Misinterpreting pH scale; remember it's logarithmic, each unit change = 10x H+.
• Overlooking water's polarity; critical for hydrogen bonding.
• Assuming enzymes change equilibrium, they only lower activation energy.
• Mistaking force units; Newton (N) = kg·m/s².
• Ignoring the hierarchical organization from atoms to systems.
• Confusing pressure units; Pa = N/m², often compare with mmHg or atm.
• Overgeneralizing fluid mechanics; viscosity varies with fluid type.
• Misunderstanding thermodynamics; energy conservation vs. entropy increase.

7. ✅ Final Exam Checklist

• Understand the scientific method and experimental design.
• Memorize SI units and their conversions.
• Be able to calculate force ($F=ma$), work ($W=Fd\cos \theta$), power ($P=W/t$).
• Know pressure formula ($P=F/A$) and units (Pa).
• Describe atomic structure and chemical bonding types.
• Explain water's properties and their biological significance.
• Understand pH scale and its biological relevance.
• Recognize enzyme function and factors affecting activity.
• Comprehend fluid mechanics principles in biological contexts.
• Differentiate between ionic and covalent bonds.
• Summarize thermodynamics principles in biological systems.
• Know the hierarchy from atoms to organ systems.
• Identify common pitfalls and clarify confusing concepts.
• Be familiar with key biological molecules and their functions.
• Understand how energy transfer sustains life processes.

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