Biology Lecture Notes: Module 6 and 7 Overview

Introduction

• Focus on revising key concepts from Module 6
• Introduction to Module 7
• Topics covered in HSC Biology syllabus:
  • Heredity
  • Genetic Change
  • Infectious Diseases
  • Non-Infectious Disease and Disorders

Module 6: Key Concepts

Mutagens

• Definition: Organisms causing mutations (also known as mutants)
• Types of Mutagens:
  • Chemical Mutagens: Radioactive agents (e.g. uranium), metals (e.g. arsenic, nickel), intercalating agents (e.g. ethidium bromide)
  • Electromagnetic Radiations: High-energy, cause DNA restructuring (e.g. UV light)
  • Natural Mutagens

DNA Mutations

• Pyrimidine Dimers: Caused by UV radiation, leads to DNA structure alteration
• Types of Mutations:
  • Point Mutations: Substitution, insertion, deletion
    • Silent Mutations: No effect on DNA
    • Missense Mutations: Change in amino acid
    • Nonsense Mutations: Premature stop codon
  • Chromosomal Mutations: Errors during meiosis, affect DNA structure
    • Types: Deletion, inversion, translocation, duplication

Effects of Mutations

• Phenotypic Expression: Changes due to mutations
• Chromosome Number Mutations:
  • Aneuploidy: Abnormal number of chromosomes (e.g. Down syndrome)
  • Polyploidy: More than two sets of homologous chromosomes (e.g. Triploidy)

Biotechnology

Impact on Biodiversity

• Types of Biotechnology:
  • Medical Biotechnology: Vaccines, antibiotics, stem cell treatments
  • Industrial Biotechnology: Biopolymers, biodegradable plastics
  • Environmental Biotechnology: Bioremediation, genetically modified organisms (GMOs)

Genetic Technologies

• Reproductive Technologies:
  • Artificial insemination, IVF, artificial pollination
• Cloning Techniques:
  • Whole organism cloning, therapeutic cloning, gene cloning
• Recombinant DNA Technology:
  • Gene sequencing, transgenesis, gene therapy, CRISPR

Exam Preparation

Example Question

• 2019 Exam Question: Application of reproductive technologies
• Structure of Answer:
  • Introduction: Define and evaluate reproductive technologies
  • Body Paragraphs: Examples and implications on genetic diversity
  • Conclusion: Reinforcement of evaluation

Module 7 Preview

• Transition to Module 7 concepts
• Continuation of biotechnology themes and genetic technologies