Chromosomal Abnormalities

• Klinefelter's Syndrome

  • Phenotypically mole
  • reduced fertility
  • some female secondary sexual characteristics
• Turners Syndrome

  • phenotypically
  • sterile
  • associated with heart defects
• Sex Chromosome

  • are generally more tolerated by organisms
• Down‘s Syndrome

  • Three copies of chromosomes 21
  • characteristics facial appearance
  • varying levels of retardation
• Single Chromosomes

  • Involve individual extra/missing chromosomes
  • usually result in early miscarriages
• Non-Disjunction

  • in nondisjunction event, chromosomes do not separate during anaphase
  • this leads to gametes with irregular number of chromosomes
• Multiple Y Chromosomes

  • the y chromosomes is the smallest human chromosome
  • it contains very few genes
  • it's major function is to direct testes formation early in development
• Multiple X Chromosomes

  • the x chromosome is pretty large
  • it contains many genes
  • BUT: both males and female have to function with it (males only only get one copy)
• Whole Sets

  • ploidy mutations
  • involve extra homologous set of chromosomes
  • usually not tolerated in animals
• Rearrangements

  • no rule about how a chromosomal rearrangement will affect an organism
  • sometimes detrimental, sometimes silent