Genetics

Study of heredity and variation in living organisms.

DNA and GenesMendelian InheritanceVariation and Mutation
Molecular GeneticsGenetic DisordersPopulation Genetics and Evolution
Genetic Testing and Personalized MedicineGenetically Modified Organisms (GMOs)Forensics and DNA Fingerprinting
Effective Note-Taking for GeneticsPracticing with Punnett Squares and ProblemsUsing Flashcards for Key Terms
DNA and GenesMendelian Inheritanc...Variation and Mutati...Molecular GeneticsGenetic DisordersPopulation Genetics ...Genetic Testing and ...Genetically Modified...Forensics and DNA Fi...Effective Note-Takin...Practicing with Punn...Using Flashcards for...
Basic Concepts

Mendelian Inheritance

The Father of Genetics

Gregor Mendel, a monk in the 19th century, was the first to discover the basic principles of heredity using pea plants.

Mendel's Laws

Mendel found that traits are inherited as discrete units, now known as genes. He described two key laws:

  • Law of Segregation: Each parent has two copies of a gene but only passes one to their offspring.
  • Law of Independent Assortment: Genes for different traits are inherited independently.

Dominant and Recessive Traits

  • Dominant traits show up if at least one copy is present (e.g., brown eyes).
  • Recessive traits only appear if both copies are recessive (e.g., blue eyes).

Punnett Squares

Scientists use Punnett squares to predict how traits will be inherited.

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BBBBb
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This helps us understand the probability of certain traits appearing in the next generation.

Examples

  • Crossing a tall pea plant with a short one produces tall offspring, showing dominance.

  • A child with two recessive alleles for blue eyes will have blue eyes.

In a Nutshell

Mendel's laws explain how traits are passed from parents to offspring.

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Variation and Mutation