Genetics and Evolution Cheat Sheet

Key Definitions

• Gene: A segment of DNA that encodes for a protein.

• 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 reproduce.

Important Concepts

Mendelian Genetics

• Law of Segregation: Alleles segregate during gamete formation.

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

Evolutionary Theories

• Darwin’s Theory: Evolution through natural selection.

• Modern Synthesis: Integration of genetics with evolution.

Key Formulas

• p: Frequency of dominant allele.

• q: Frequency of recessive allele.

p² + 2pq + q² = 1

• p²: Frequency of homozygous dominant genotype.

• 2pq: Frequency of heterozygous genotype.

• q²: Frequency of homozygous recessive genotype.

Common Mistakes to Avoid

Common Mistake: Confusing genotype with phenotype; remember genotype is genetic makeup, phenotype is expression.

Memory Tricks

Tip: "GAMETES" —

• G: Genes

• A: Alleles

• M: Mendel

• E: Evolution

• T: Traits

• E: Environment

• S: Selection

Key Diagrams

Punnett Square:
+---+---+---+
| A | a |
+---+---+
| A | AA| Aa|
+---+---+
| a | Aa| aa|
+---+---+

Evolutionary Tree:
        ┌── Species A
    ┌───|
    |   └── Species B
───|       
    |   ┌── Species C
    └───|
        └── Species D