GAMSAT Section 3 Biology Crash Course

Introduction

• Presenter: Jesse, GAMSAT tutor from Melbourne
• Purpose: Condense essential biology concepts for the GAMSAT into a short and high-yield crash course
• Format: 4 installments, covering key biological concepts needed for GAMSAT

Key Concepts Covered

Gene Expression

• Gene Expression: Process of converting DNA into a functional protein
• Steps:
  1. Transcription: DNA to mRNA
     • DNA is transcribed by RNA polymerase into mRNA
     • mRNA is complementary to the template strand of DNA
     • Important concepts: Transcription, Template Strand, RNA Polymerase
  2. Translation: mRNA to Polypeptide
     • mRNA sequence read by ribosome, tRNA brings amino acids to form polypeptide
     • Codons on mRNA match anticodons on tRNA
     • Important concepts: Codons, Anticodons, Ribosome

Enzyme Activity

• Enzymes: Proteins that act as biological catalysts
• Functions:
  • Increase reaction rate
  • Decrease activation energy
• Factors Affecting Enzymes:
  • Temperature: Optimal range for activity, too high leads to denaturation
  • pH: Specific range required, deviations lead to denaturation
• Active Site: Part of the enzyme where substrate binds

Hormonal and Neural Maps

• Hormonal Maps: Analyze pathways of stimulation and inhibition
  • Stimulation: Positive impact, increases downstream reactions
  • Inhibition: Negative impact, decreases downstream reactions
• Neural Maps: Similar analysis method as hormonal maps
  • Understand excitatory (stimulatory) and inhibitory pathways

Metabolism and Photosynthesis

• Metabolism: Breakdown and synthesis of compounds
  • Catabolism: Breakdown of molecules for energy
  • Anabolism: Synthesis of molecules from simpler ones
  • Glucose metabolism involves glycolysis, Krebs cycle, and electron transport chain
• Photosynthesis: Process by which plants convert light energy into chemical energy
  • Occurs in chloroplasts, involves transformation of CO2 and H2O into glucose
  • Plants have added capability to synthesize their own food using sunlight
  • Photosynthesis chemical equation: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

Conclusion

• Biology in GAMSAT is more skill-based than theory-based
• Emphasis on problem-solving and applying reasoning
• Theory supports faster processing of questions but is not the main focus
• Upcoming series on Math Crash Course