Biology #4

• Genes

  • functional unit of heredity found in chromosomes which are in the nucleus of a cell.
• Cell

  • All living things are made of this
• Organelles.

  • Inside the cell are smaller structures
• Nucleus

  • controls and regulates the activities of the cell.
  • contains the hereditary materials.
• Chromosomes

  • Inside the nucleus are thread like structure that contains genetic materials.
• Parts of a cell:

  1. Nucleus
  2. Chromosomes
• 3 Types of Chromosomes:

  1. Chromatin
  2. Chromosomes
  3. DNA
• Chromatin

  • unraveled condensed structure of DNA.
• Chromosomes

  • highly condensed structure of DNA.
• DNA

  • long molecules that contains our genetic code; hereditary materials in humans and almost all others.
• Genes

  •  long segment of the chromosomes/DNA that codes for a certain trait.
• Chromosomes and genes

  • Humans have 46 chromosomes or 23 pairs of chromosomes 
  • Chromosomes come in pairs; they are called homologous chromosomes
• Karyotyping

  • A photograph of all chromosomes in a cell arranged in pairs.