Meiosis | Cell division resulting in four genetically unique daughter cells [gametes] each with half the number of chromosomes [haploids] as the parent cell [diploids] |
Crossing Over + Recombination | - Occurs during Prophase I
- Homologous Chromosomes: each consisting of two sister chromatids, line up together forming a tetrad
- One chromatid from each homologous pair cross over at points called chaisma, and genes/alleles are exchanged |
Definition of Spermatogenesis | Production of sperm from spermatogonia |
Definition of Oogenesis | Production of eggs form oogonia |
Location of Spermatogenesis | Testes |
Location of Oogenesis | Ovary |
Continuity of Spermatogenesis | Continuous since puberty |
Continuity of Oogenesis | Discontinuous process: early stages in faetus, continuing post puberty |
Cytokinesis of Spermatogenesis | Four haploid sperm cells produced [4 spermatozoa] |
Cytokinesis of Oogenesis | One oogonium produces one ovum, and three polar bodies which get degraded and reabsorbed. |
Independent Assortment | Chromosomes and associated genes separate independently from non-homologous chromosomes when gametes form |
Random Fertilisation | Unpredictable union of gametes during sexual reproduction, contributing to genetic diversity in offspring through the chance combination of different alleles from each parent. |
Fertilisation | Fusion of two haploid gametes results in the formation of a diploid zygote → zygote divides to multiply, producing an embryo. |