Meiosis
Jan 01, 2016
• The process where gametes are formed
• 2 stages of cell division (some similarities to the phases in mitosis)
• The chromosome number of the daughter cell is half of the parent cell
• A gamete has n number of chromosomes (a hapliod number)
• Somatic cells (all other cells) have 2n number of chromosomes (a diploid number)
What is it?
Parents and Offspring
• In humans, the haploid chromosome number is 46, and the diploid number is 23
• Offspring have genetic information from both of their parents (23 from each)
• Each of the 23 chromosomes from the mother is matched with 23 chromosomes from the father
Homologous chromosomes
• Paired chromosomes are called homologous chromosomes
• Homologous chromosomes interact during meiosis and your characteristics are determined by how they interact
• This interaction is called crossing over and happens during prophase I of meiosis
Fertilization
• During fertilization in humans, a haploid (n=23) sperm cell unites with a haploid (n=23) egg cell
• A diploid (2n=46) zygote is produced from this union
Zygote