Meiosis
Table of Contents
Definition
- also known as "_Reduction-Division Genetic Recombination_"
- the form of cell division by which gametes, with half the number of chromosome.
- Occurs only in Gonads (testes or ovaries).
Gametes
- is a haploid cell (n) that fuses with another haploid cell during fertilization to form a zygote.
- it is an organism's reproductive cells/sex cells.
Spermatogenesis
- formation of sperm cells.
Oogenisis
- formation of egg or ova (plural of ovum).
Phases
Karyotype
- An organized picture of the chromosomes of a human arranged by size from largest to smallest.
Autosomes
- Pairs 1 - 22
Sex Chromosomes
- last pair
Fertilization
- A zygote is a fertilized egg
Non-disjunction
- failure of homologous chromosomes or sister chromatids to separate during meiosis.
- results with the production of zygotes with abnormal chromosomes numbers
Trisomy
2n + 1
Trisomy-13
- Patau's Syndrome
Trisomy-18
- Edward's Syndrome
Trisomy-21
- Down Syndrome
Trisomy-23 (XXY)
- Klinefelter's Syndrome
Trisomy X (47,XXX)
- An extra X chromosome
Monosomy
2n - 1
Monosomy-23 (X0)
- Turner's Syndrome
Jacob's Syndrome
- An extra Y chromosome
Frequency
- 1 in every 1000 male births