Module 1 - Unit 2

Meiosis = A reduction division. The production of cells that are genetically different from each other and from the parent cell. The resulting daughter cells have half the original number of chromosomes compared to the parent cell --> they are haploid. 

Haploid = One set of chromosomes. One chromosome from each pair. Expressed: n.

Mitosis = The production of cells that are genetically identical to one another and the parent cell. Genetic mutation results in variation. 

Diploid = Two sets of chromosomes. (One from the mother and one from the father) Expressed: 2n.

Bivalent = A pair of joined homologous chromosomes during Prophase 1 and Metaphase 1.

Crossing-over = When non-sister chromatids exchange alleles during Prophase 1 of Meiosis. 

Chiasmata = The points were non-sister chromatids within a bivalent join, where they cross over.

Homologous pairs = Two chromosomes that pair up during Meiosis. They have the same genes at the same loci, but different alleles. 

Sister Chromatids = A replicated chromosome that has two identical strands and is joined by a common centromere.