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

DNA and Genes

What is DNA?

DNA (Deoxyribonucleic Acid) is the molecule that contains the instructions an organism needs to develop, live, and reproduce. It's like a recipe book for building a living thing!

  • DNA is made up of four chemical bases: Adenine (A), Thymine (T), Cytosine (C), and Guanine (G).
  • The sequence of these bases forms genes, which are specific instructions for making proteins.

Genes: The Instructions for Life

Genes are sections of DNA that code for proteins. These proteins perform most life functions and make up the majority of cellular structures.

  • Humans have about 20,000-25,000 genes!
  • Genes are inherited from our parents, which is why we often resemble them.

How Does DNA Work?

DNA has a double helix structure. Each base pairs with a partner (A with T, C with G), creating the famous twisted ladder shape.

Why is DNA Important?

DNA is the foundation of genetics. Understanding it helps us explore how traits are passed from parents to offspring and how variations arise.

Fun Fact

If you stretched out all the DNA in your body, it would reach from the Earth to the Sun and back—over 600 times!

Examples

  • A child inherits brown eyes from one parent and curly hair from another due to specific genes.

  • Genetic disorders like cystic fibrosis are caused by mutations in certain genes.

In a Nutshell

DNA is the blueprint of life, and genes are its instructions.

Key Terms

Gene
A segment of DNA that codes for a specific protein.
DNA
The molecule that carries genetic information in living organisms.
Mutation
A change in the DNA sequence, which can lead to variation.
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Mendelian Inheritance
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