Hoja de repaso: Fundamentals of Biological and Physical Sciences

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

Item	Key Features	Notes / Differences
Ionic Bond	Transfer of electrons, forms charged ions	Strong in salts, dissolves in water
Covalent Bond	Sharing of electrons, forms molecules	Can be polar or nonpolar
Acid (low pH)	Donates H+ ions, increases H+ concentration	Example: HCl
Base (high pH)	Accepts H+ ions, decreases H+ concentration	Example: NaOH
Water (H₂O)	Polar molecule, high specific heat, solvent capacity	Facilitates biochemical reactions

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.

---