Grade 12 Biology Genetics Study Guide

Major Concepts

1. Inheritance Patterns and Chromosomes

• Mendel's Laws of Inheritance:

  • • Law of Segregation: Each organism carries two alleles for each trait, which segregate during gamete formation.

    • Law of Independent Assortment: Alleles of different genes assort independently during gamete formation.

• Monohybrid and Dihybrid Crosses:

  • • Monohybrid Cross: Involves a single trait (e.g., seed color in pea plants).

    • Dihybrid Cross: Involves two traits (e.g., seed color and seed shape).

• Punnett Squares:

  • • Used to predict the genotypic and phenotypic outcomes of genetic crosses.

2. Molecular Genetics and Mutations

• Structure and Function of DNA and RNA:

  • • DNA: Composed of nucleotides (adenine, thymine, cytosine, guanine) and forms a double helix.

    • RNA: Typically single-stranded, with uracil instead of thymine.

• DNA Replication, Transcription, and Translation:

  • • DNA Replication: Ensures genetic continuity.

    • Transcription: DNA to RNA.

    • Translation: RNA to protein.

• Mutations:

  • • Changes in DNA sequences that introduce genetic variation, crucial for evolution.

3. Environmental and Epigenetic Factors

• Environmental Influences on Gene Expression:

  • • Factors like diet, toxins, and stress can alter gene expression without changing the DNA sequence.

• Epigenetics:

  • • DNA Methylation, Histone Modification, Non-coding RNAs: Mechanisms that regulate gene expression.

• Impact on Health and Disease:

  • • Epigenetic changes can contribute to diseases such as cancer, diabetes, and mental health disorders.

4. Biotechnology and Ethics

• Historical Milestones in Biotechnology:

  • • Discovery of DNA Structure, Development of PCR, Creation of Recombinant DNA.

• Current Applications:

  • • GMOs, CRISPR-Cas9 Gene Editing, Gene Therapy, Bioremediation, Vaccines, and Medicines.

• Emerging Technologies:

  • • Synthetic Biology, Personalized Medicine, Gene Editing, Bioprinting.

• Intellectual Property and Regulation:

  • • Patents, Trademarks, Copyrights, Trade Secrets.

    • Regulatory Frameworks: Health Canada, CEPA, Novel Foods Regulations.

Key Terms

• Allele: Different forms of a gene.

• Genotype: Genetic makeup of an organism.

• Phenotype: Observable traits of an organism.

• Homozygous: Two identical alleles for a trait.

• Heterozygous: Two different alleles for a trait.

• Meiosis: Cell division process that results in four haploid gametes.

• DNA Methylation: Addition of methyl groups to DNA, turning genes off.

• Histone Modification: Changes to histone proteins, affecting DNA accessibility.

• CRISPR-Cas9: Gene editing technology.

Skills

• Using Punnett Squares:

  • • Predicting genotypic and phenotypic ratios for monohybrid and dihybrid crosses.

• Analyzing Genetic Crosses:

  • • Understanding inheritance patterns using Mendel’s laws.

• Use a Codon Wheel

  • • Be able to use a Codon wheel to predict what DNA and RNA will make a certain protein

• Understanding Epigenetic Mechanisms:

  • • Identifying how environmental factors can influence gene expression.

• Evaluating Biotechnological Advances:

  • • Understanding the applications and ethical considerations of current and emerging biotechnologies.