Exam 1

🧬 Chapter 1: The Study of Life

Key Concepts:

• Characteristics of Life:
  
  

  • Made of cells, responds to stimuli, maintains homeostasis, grows and develops, reproduces, processes energy, evolves.
    
    

• Levels of Biological Organization:
  
  

  • Atom → Molecule → Cell → Tissue → Organ → Organ System → Organism → Population → Community → Ecosystem → Biosphere
    
    

• Scientific Method Steps:
  
  

  • Observation → Hypothesis → Experiment → Data → Conclusion → Publish
    
    

• Homeostasis:
  
  

  • Body’s ability to maintain internal balance (e.g., temperature, pH).
    
    

  • Maintained through negative feedback mechanisms.
    
    

• Anatomy vs Physiology:
  
  

  • Anatomy = structure, Physiology = function.
    
    

Study Tips:

• Practice explaining the scientific method with an example.
  
  

• Use diagrams to understand levels of organization.
  
  

• Know real-life examples of homeostasis (like sweating or insulin control).
  
  

⚛ Chapter 2: Basic Chemistry

Key Concepts:

• Atoms and Elements:
  
  

  • Atoms consist of protons (+), neutrons (0), electrons (–).
    
    

  • Atomic number = # of protons; Mass number = protons + neutrons.
    
    

• Chemical Bonds:
  
  

  • Ionic bonds: transfer electrons (e.g., NaCl).
    
    

  • Covalent bonds: share electrons (e.g., H₂O).
    
    

  • Hydrogen bonds: weak, between polar molecules (e.g., water).
    
    

• Water Properties:
  
  

  • Cohesion, adhesion, high heat capacity, universal solvent.
    
    

  • Polarity of water = key to its behavior.
    
    

• pH Scale:
  
  

  • Measures hydrogen ion concentration.
    
    

  • 0–6 acidic, 7 neutral, 8–14 basic.
    
    

  • Buffers resist pH changes in the body.
    
    

Study Tips:

• Practice identifying types of bonds in molecules.
  
  

• Understand how water’s polarity leads to hydrogen bonding.
  
  

• Review the significance of pH in biological systems.
  
  

🍞 Chapter 3: The Chemistry of Organic Molecules

Key Concepts:

• Macromolecules and Monomers:
  
  

  • Carbohydrates → monosaccharides (e.g., glucose)
    
    

  • Lipids → fatty acids and glycerol
    
    

  • Proteins → amino acids
    
    

  • Nucleic acids → nucleotides (DNA & RNA)
    
    

• Functions of Macromolecules:
  
  

  • Carbs = energy; Lipids = energy storage, insulation; Proteins = enzymes, structure; Nucleic acids = genetic code.
    
    

• Enzymes:
  
  

  • Biological catalysts, speed up reactions.
    
    

  • Active site binds substrate; affected by pH and temperature.
    
    

• Dehydration Synthesis vs Hydrolysis:
  
  

  • Dehydration: links monomers, removes water.
    
    

  • Hydrolysis: breaks bonds, adds water.