IB BIO 10.1- Meiosis

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7/26/2019 IB BIO 10.1- Meiosis

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10.1- MeiosisYoel Alperin and Hill Belfi

Meiosis he !eduction of the nucleus to form haploid gametes"

#A$%! DI&&'!'NC'( NOT A CYCLE

Chromosome Descriptions

)I*A+'N

,AI! %& SIS'! CH!%#%S%#'S

Prophase I

Nuclear membrane dissolves

Centrioles move to the poles

Homologous chromosomes associate and and become bivalent

Crossing over and synapsis

Crossing Over

/0 Synapsis- homologous chromosomes associate

10 Chiasma &ormation- neighboring non-sister chromatids are exchanged

20 !ecombination-alleles are swapped

Linked enes Diagram

!nimation

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Metaphase I

!andom orientation occurs along e;uator

89< chance of going to a particular pole =Independent of each other0

(orld Conte)t

his section has shown multiple ways in which nature tries to

increase variety in populations and we have seen the power of

variation in natural selection" Despite our understanding of the

importance of variation for natural selection biodiversity and for ourhealth countries all over the world are reducing the variety of crops

they plant and are replacing balanced ecosystems with

monocultures" Are such practices sustainableB Could reducing

variety in the foods we grow and eat increase ris>s of famine and

other global health crisesB

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