BIOL 202 Lecture Notes - Lecture 16: Homologous Chromosome, Ploidy, Colchicine
Document Summary
Complete sets chromosome (each pair/group of homologous chromosome contains the same number of chromosomes) Can be monoploid/haploid, diploid, triploid, tetraploid : aneuploidy. One or more chromosome missing/having one extra chromosome. Chromosome number can be expressed as 2n+1 or 2n-1: autopolyploids. The sets of chromosome come from the same species: allopolyploids. Error in segregation in meiosis: one gamete gets both sets of chromosomes. Egg fertilized by 2 sperms: or made by deliberate genetic engineering. Tetraploid parent (2n gamete) and diploid parent (n gamete) produce triploid zygote: triploids are inviable in human and rarely occurs, some frogs, toads are triploid, can be used for commercial purpose. E. g. triploid oyster is bigger than diploid oyster (the cells are bigger, and the whole organism is bigger too) E. g. banana and seedless watermelons (these plants are sterile because they have dysfunctional gametes: higher ploidy is more common in plants.
