Genetics Basics

Genetics

Key Concepts

• Genetics: the study of heredity, genes, and genetic variation
• Genome: complete set of genetic information in an organism
• Gene: basic unit of heredity, carries information from one generation to the next
• Genotype: genetic makeup of an individual
• Phenotype: physical and behavioral characteristics of an individual

DNA Structure

• Double Helix Model: DNA molecule shaped like a twisted ladder
• Nucleotides: building blocks of DNA, consisting of:
  • Sugar molecule (deoxyribose)
  • Phosphate group
  • Nitrogenous base (A, C, G, or T)
• Base Pairing: adenine (A) pairs with thymine (T), guanine (G) pairs with cytosine (C)

Inheritance Patterns

• Mendel's Laws: principles of inheritance discovered by Gregor Mendel
  • Law of Segregation: each trait is determined by two alleles
  • Law of Independent Assortment: alleles for different traits are sorted independently
• Dominant and Recessive Traits: dominant traits are expressed when paired with a recessive allele
• Incomplete Dominance: one allele is not completely dominant over the other
• Co-Dominance: both alleles are equally expressed

Genetic Variation

• Mutations: changes in DNA sequence, can result in genetic variation
• Genetic Drift: random events that change allele frequencies in a population
• Gene Flow: movement of genes from one population to another
• Natural Selection: process by which populations adapt to their environment

Genetic Analysis

• Karyotyping: visual representation of an individual's chromosomes
• Genetic Testing: analysis of DNA or RNA to diagnose genetic disorders
• Genetic Engineering: manipulation of an organism's genome using biotechnology