Science

• DNA

  molecules packed into thread like structures called chromosomes
• what is a gene

  is the base unit of heredity
• cell devision

  interphase - praphase - metaphase - anapahse - telephase
• mitosis

  produces 2 daughter cells found in your somatic cells, involved in growth anf repair of the body
• meiosis

  produces the reproductive cells in organisms, the end result is 4 distict daughter cells
• dna repliation

  helicase breaks down the bonds between the complementray pair

  dna polymerase adds nucleotide to the complemtray base
• who founded the double helix model of dna

  Waston and Crick founded it in 1953 by a xray crystallography
• mutation 


  can happen by chance or due to interactions with chemicals or radiation

  deletion - removed

  subsitution - replaced

  insertion - added
• pedigrees

  studying family history to find built up patterns of inheritence (roman numerals used for generations)

  squares - males

  circle - female

  horizontal line - mariage

  veritcle line - children

  coloured - gene inherited
• fingerprinting pros and cons

  pros

  • crime investigation
  • evolutionary study
  • parental disputes

  cons

  • misused
  • easy access
  • voilation of indiviuals right
• what is dna finger printing

  biotechnology used to determine genetic composition of an indiviual based on unquie difference in our dna
• process of mitosis

  a eukaryotic cell nucleus splits in 2, followed by the division of the parent cell into 2 daughter cell

  • 2 pairs of chromosomes
  • the chromosomes are doubled
  • line upon the ‘equater‘ of the cell
  • seperate and move to end of cell
• process of meiosis

  single cell divides twice to produce 4 cells containing half the amount of genetic information

  • 2 pairs of viable chromosomes
  • chromosomes are doubled
  • homologous chromos line upon the ‘equator’
  • move to the edge of the cell
• punnet squares

  genotype: Allele result (BB, bb Bb)

  phenotype: the characteristics (black hair)

  homozygous- 1

  heterozygous 2
• DNA 


  deoryribonuclelic acid

  phosphate and sugar base

  adenine = thymine

  cytosine = guanine