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Stages of Meiosis


DNA replicates → Identical sister chromatids form


Meiosis I

Meiosis II (same as mitosis)


//Spindle forms
Nuclear envelope disappears
- Chromosomes shorten/thicken/condense
- Form bivalents/tetrads
Crossing-over of homologous pairs

//Spindle forms
//Nuclear envelope disappears


//Spindle complete
- Bivalents at equator
- Join to spindle (fibres) via centromere

//Spindle complete
- Chromosomes at equator


//Cytokinesis begin
Random segregation of homologues
- Intact centromeres
- Two chromatids on one chromosome

//Cytokinesis begins
Random segregation of chromatids
- Chromatids are pulled to opposite poles
- Centromeres divide


//Spindle disappears
//Nuclear envelope reforms
- 2 haploid cells
- Chromosomes still duplicated

//Spindle disappears
//Nuclear envelope reforms
4 haploid daughter cells

Principles of Mendelian Inheritance

Multiple Alleles

Codominance (1:2:1)

Sex Linkage

Application of Chi-Squared Test (x²) to Data Obtained