3,4.3 genetic diversity

Question 1

what stage does inependant segregation and crossing over occur in

Answer 1

meiosis one

Question 2

name all 4 things that cause genetic diversity

Answer 2

independant segregation
crossing over
random fertilization
mutations

Question 3

differences between meiosis and mitosis

Answer 3

meiosis - 2 divisions, 4 haploid cells, genetic diversity
mitosis- one division, 2 diploid cells, identical

Question 4

describe what happens in independent segregation

Answer 4

in metaphase 1 of meiosis 1, homologous chromosome pairs line up randomly along the equator
in anaphase 1, each pair separates independently, creating different combinations of maternal and paternal chromosomes in gametes.

Question 5

describe what happens in crossing over

Answer 5

in prophase 1, homologous chromosomes pair up and exchange segments at points called chiasmata
creates new allele combinations, increasing genetic diversity

Question 6

describe natural selection

Answer 6

variation exists due to mutations and meiosis.
selectional pressures favours individual with advantageous alleles.
survive longer and reproduce more
over many generations, beneficial allele inceases in frequenncy.

Question 7

what is non-disjunction

Answer 7

when the chromosomes or chromatids do not split equally during anaphase.