Meiosis
Haploid
1 set of chromosomes (n)
Diploid
2 sets of chromosomes (2n)
result of meiosis
4 haploid cells
Spermatogenesis
Formation of sperm
metaphase 1
Spindle fibers attach to the chromosomes and then tetrads will line up along the metaphase plate
anaphase 1
Spindle fibers move homologous chromosomes to opposite sides
anaphase 2
chromatids separate and move to opposite poles
metaphase 2
chromosomes line up, sister chromatids are not genetically identical
What does crossing over do?
increase genetic variation
Telophase 1
nuclear membrane forms around each set of chromosomes, and the cytoplasm divides forming two daughter cells
Gamete
sex cell, contains 23 chromosomes in humans
prophase 2
spindle reforms, nuclear membrane disappears
Tetrad
structure containing 4 chromatids that forms during meiosis
Oogenesis
Egg production
telophase 2
A nuclear membrane re forms, cytoplasm pinches in
polar bodies
Cells produced in females that do not participate in reproduction
Interphase 1
Cells undergo a round of DNA replication, forming duplicate chromosomes
homologous chromosomes
Chromosomes that have the same sequence of genes and the same structure
prophase 1
Crossing over occurs
somatic cells
body cells, contains 46 chromosomes in humans