meiosis- gamete formation mader chapter 17.3. mitosis does not alter the chromosomal makeup of cells
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Meiosis- gamete formation
Mader Chapter 17.3
Mitosis does not alter the chromosomal makeup of cells
Chromosome number must be reduced when gametes are produced
Meiosis separates homologous chromosomes
There are 2N Possible arrangements of homologues
Humans have 23 pairs of homologous chromosomes N=23There are 223 possible arrangements of homologues = 8,388,608
Four of the eight possible arrangements for a N = 3 organism are shown above. Each Arrangement2 gametes so there are 8 possible gametes!
Crossing over generates even more diversity
Meiosis
Separates homologous chromosomes Chromosome number goes from 2N N Generates a very diverse set of gametes
each of which contains a nearly unique set of maternal and paternal genes
Spermatogenesis
Human ova are ovulated arrested in meiotic prophase II
The human life cycle
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