dna one - chromosomes, genome & migration

    Cards (13)

    • DNA
      Deoxyribonucleic acid, the chemical that all of our genetic material is made of
    • DNA
      • DNA is a double helix polymer, which means it is a polymer made up of two strands forming a twisted, ladder shape.
    • If you unraveled all the DNA in a single cell, the strand would be over two meters long
    • Chromosome
      A really tight coil of DNA, there are 46 chromosomes in each of our cells
    • There are only 23 different types of chromosomes, as we have two of each type (one from each parent)
    • Sex chromosomes

      The 23rd pair of chromosomes, consisting of an X chromosome and a Y chromosome
    • Females have two X chromosomes, while males have one X and one Y chromosome
    • Chromosomes only look like an 'X' shape just before cell division, usually they look more like tight 'l' shaped coils
    • Gene
      A gene is a small section of DNA. Genes code for a sequence of amino acids, which combine to give a specific protein.
    • There are only 20 different types of amino acids, but they can be combined in many different sequences to form thousands of different proteins
    • Genome
      The entire set of genetic material in an organism
    • Scientists have now worked out the complete human genome, which allows them to identify genes linked to certain diseases
    • Genomes can be used to trace the migrations of our ancestors by looking at small differences between populations