Mitosis vs meiosis

Differences between mitosis and meiosis

View animations and movies on -the differences between- mitosis and meiosis.
 
MITOSIS
MEIOSIS
In somatic cells
In reproductive cells
One single division (here below A-E) of the mother cell (m) results in two daughter cells (d)mitosis mother- and daughter cellTwo divisions (here below: meiosis I in A-E and meiosis II in F-H) of the mother cell (meiocyte; m) result in four meiotic products (p)Meiocyte and meiotic products
mitosis diagram meiosis diagram
A mitotic mother cell can be either haploid or diploidmitosis mother and daughter cellA meiotic mother cell (meiocyte) is always diploidMeiocyte en meiotic products
The number of chromosomes per nucleus remains the same after division Diploid (= 2n) remains 2n
Haploid (= 1n) remains 1 n
The meiotic products contain a haploid (n) number of chromosomes, in contrast to the 2 n mother cellFrom 2n to n
Mitosis is preceeded by a S-phase in which the amount of DNA is duplicated Example for a diploid mother cell:
DNA amount in mitosis
Only meiosis I is preceeded by a S-phaseDNA amount in meiosis
Normally no pairing of homolog chromosomesxComplete pairing of all homolog chromosomes during prophase I Pairing of homolog chromosomes during prophase I
Normally no exchange of DNA (crossing-over) between chromosomesxAt least one crossing-over per homolog pair of chromosomes meiosis: crossing-over
The centromeres are split during anaphaseMitose: anafase splitsing centronerenThe centromeres do not separate during anaphase I, but during anaphase II Meiose: anafase II alleen splitsing centroneren
Conservative process: the genotype of the daughter cells is identical to that of the mother cellsmitosis: identical genotype mother and daughter cellsMeiotic products differ in their genotype from the mother cell (increase in genetic variation in the offspring) meiosis: non-identical genotype mother and daughter cells

 
The mitotic metaphase can be distinguished from the metaphase I of meiosis as no pairing of homolog chromosomes occurs in mitosis; this is not necessary, even not suitable for the mitotic process (why?). Further, homolog chromosomes separate during metaphase I of meiosis, whereas during mitosis and metaphase II the separating structures are the chromatides. The difference between the separation in mitosis and metaphase II (meiosis) is that halfing of the number of chromosomes has preceeded meiosis II, in contrast to mitosis. Also the meiotic products are genetically diverse with respect to their parent and among each other. This is not the case in mitosis!

http://www.vcbio.science.ru.nl/en/virtuallessons/cellcycle/mitomeio/print/

last modified: 14 Oct 2011