Fundamentals of Genetic Structure and Function

📋 Course Outline

1. Structure of DNA
2. DNA Replication Process
3. Polymerase Chain Reaction
4. Gene Expression Mechanisms
5. Cellular Differentiation and Stem Cells
6. Genome Structure and Non-coding DNA
7. Mutations and Chromosome Changes
8. Evolution and Natural Selection
9. Genomic Sequencing and Phylogenetics

📖 1. Structure of DNA

🔑 Key Concepts & Definitions

• Double-helix structure of DNA: DNA is composed of two strands that wind around each other in a spiral form, creating a double-helix shape. The strands are arranged in an anti-parallel manner, meaning they run in opposite directions.

• Nucleotides composition: A DNA nucleotide consists of three components:

  • Deoxyribose sugar: A five-carbon sugar molecule that forms part of the nucleotide backbone.
  • Organic Base: A nitrogen-containing base (Adenine, Thymine, Cytosine, or Guanine).
  • Phosphate group: A chemical group that links nucleotides together.

• Anti-parallel strands in DNA: The two DNA strands run in opposite directions; one strand runs from the 3’ end to the 5’ end, and the other from 5’ to 3’. This orientation is crucial for DNA replication and function.

• Sugar-phosphate backbone formation: The deoxyribose sugar of one nucleotide is covalently bonded to the phosphate group of the next nucleotide, forming a continuous chain. This creates the structural framework of DNA, known as the sugar-phosphate backbone.