DNA, genes and chromosomes

• what is DNA?

  • 2 strands coiled together - form double helix
• what are chromosomes?

  • DNA separated into 46 different sections which have tight coils
  • there are 45 chromosomes - 23 different types - 2x each type - one for each parent
  • huaman's have diploids
  • 23 pair of chromosomes is the sex chromosomes determine if you are male (XY) or female (XX)
• what is Gene?

  • small section of DNA that codes for a protein
  • codes for sequence of amino acids - combined to form protein
  • 20 different types of amino acids - lots of combinations allow thousands of different proteins
  • DNA determines what type of protein is made and what type of cell it is
• what is a genome?

  • entire set of genetic material of an organism
  • can trace migration of ancestors
  • may increase risk of disease