DNA, Chromosomes, and Genes

• DNA

  • Deoxyribonucleic acid
  • the chemical inside of the nucleus of the cell that carries the genetic instructions for making a living organism.
• Chromosomes

  • threadlike “packages” and other DNA in the nucleus. Different organisms have different numbers of chromosomes.
• Chromosomes

  • Humans have 46 chromosomes (23 chromosome pairs), 44 autosomes or body cells, and two sex chromosomes.
• Genes

  • a functional and physical unit of heredity passed from parent to offspring. These are pieces of DNA and contain information for making a specific protein.
• Genome

  • all the DNA contained in an organism or a cell, which includes the chromosomes and (DNA in the chloroplasts of plant cells).