Lecture Notes: The Human Body and Cellular Structure

Overview

• The human body is composed of different tissues, each with specialized functions.
• Focus on the liver as an example of tissue specialization.

Cellular Structure

• Tissues: Made up of specialized cells.
• Liver Cell: Example of a specialized cell.

Organelles

• Specialized structures and compartments within cells.
• Nucleus: Contains the genome.

Genome and Chromosomes

• Genome: Packaged within the nucleus.
• Organized into structures called chromosomes.
• Chromosomes: 23 pairs in total.
  • Includes two sex chromosomes.
  • Women: XX chromosomes.
  • Men: XY chromosomes.

DNA Structure

• Chromosomes consist of tightly coiled DNA forming chromatin loops.
• Nucleosomes: DNA wrapped around proteins called histones.
• DNA: Double helix structure, similar to a twisted ladder.
  • Made up of four bases: Adenine (A), Cytosine (C), Guanine (G), and Thymine (T).
  • Base Pairing: A pairs with T, C pairs with G.

Genetic Information

• The sequence of DNA bases carries instructions for cell behavior and function.
• Genes: Specific DNA sections with instructions for producing molecules.
• Human genome contains approximately 23,000 genes.

Genome Analogy

• Encyclopedia Analogy:
  • Genome is compared to an encyclopedia.
  • Chromosomes are the books that make up the encyclopedia.
  • Printing the entire human genome (3 billion letters) would require 120 books.