The OTHER way to divide

MeiosisMeiosis is another process of cell division. It is very similar to Mitosis and shares the

divisional phases.Unlike Mitosis the genetic material being

divided is similar but NOT exactly identical

Mitosis (Short Simple and Sweet)Cell division of Diploid cellsCells that are created are exact copies of the

original.The Mother Cell creates 2 Daughter Cells

with the same amount of Chromosomes (2N) as the original.

Mitosis (Short Simple and Sweet)Interphase consists of 4 Phases: G1, S, G2

and G0 During interphase cell grows in size and

determines if it can begin Mitosis.

Mitosis follows Interphase and consists of 4 Phases: Prophase, Metaphase, Anaphase and Telophase

Mitosis CycleProphase: Chromosomes condense Body

spindles relocate, Nucleus dissolvesMetaphase: Chromosomes align at EquatorAnaphase: Chromatids separate and head to

opposite polesTelophase: Chromatids reach poles and cell

pinches creating two daughter cells

The Stages of Meiosis

Meiosis Meiosis is used during sexual reproduction.Meiosis uses Haploid cells from a mother

and father to create the first human cell.

The mother donates the Oocyte (egg cell)The Father donates the Spermacyte (sperm)

MeiosisMeiosis uses the same 4 Phases as Mitosis but it goes through the division process 2x

Meiosis IProphase, Metaphase, Anaphase, Telophase

Meiosis IIProphase II, Metaphase II, Anaphase II and Telophase II

The Beginning

The Cell begins by combining 23 Chromosomes from the mother (oocyte) and

father (spermacyte)

The Newly developed Cell has 46 Chromosomes (2N) @ Interphase

Prophase

During Prophase the Chromosomes duplicate and join in homologous pairs.

Homologous Chromosomes – Chromosomes of similar size, length and shape that display the same genes.

23 Homologous pairs

ProphaseAfter Joining in Homologous pairs the cells

then begin to Crossover

During Metaphase the Homologous pairs align at the Equator and stick near their matching counterpart.

During Anaphase one of the haploid pairs get pulled to a different pole

During Telophase the chromosomes are enclosed in the nuclear membrane but do not untangle

Meiosis IIFollows shortly behind Meiosis I

The process is similar to mitosis with different genetic results.There is NO Crossover or Chromosome Duplication!!!!The end result is production of four haploid cells (23 chromosomes, N) from the two haploid cells produced in meiosis I.

Crash Course Meiosis