Genetics and Evolution Cheat Sheet

Key Definitions

• Gene: A segment of DNA that encodes a protein or functional RNA. ✅

• Allele: Different forms of a gene. ✅

• Genotype: The genetic makeup of an organism. ✅

• Phenotype: The observable traits of an organism. ✅

• Natural Selection: Process where organisms better adapted to their environment tend to survive and produce more offspring. ✅

Important Concepts

Mendelian Genetics

• Law of Segregation: Alleles separate during gamete formation. ✅

• Law of Independent Assortment: Genes for different traits are inherited independently. ✅

Evolutionary Mechanisms

• Mutation: A change in DNA sequence that can lead to new traits. ✅

• Gene Flow: Transfer of alleles between populations. ✅

• Genetic Drift: Random changes in allele frequencies, especially in small populations. ✅

Key Formulas

• Hardy-Weinberg Principle: p² + 2pq + q² = 1

• p: frequency of dominant allele

• q: frequency of recessive allele

Common Mistakes to Avoid

Common Mistake: Confusing genotype with phenotype; remember genotype refers to genetic makeup, while phenotype refers to observable traits.

Memory Tricks

Tip: "GAMETES" —

• G: Genes

• A: Alleles

• M: Mendelian

• E: Evolution

• T: Traits

• E: Environment

• S: Selection

Key Diagrams

      Alleles
        A  a
        |  |
      ---------
      |       |
      |       |
      |       |
      ---------
      Gametes

  Evolutionary Tree
    ┌─ Species A
    │
───┤
    │   ┌─ Species B
    └───┤
        │   ┌─ Species C
        └───┤
            └─ Species D

Tip: Review evolutionary trees for understanding relationships among species.