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)		Two 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)
A mitotic mother cell can be either haploid or diploid		A meiotic mother cell (meiocyte) is always diploid
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 cell	From 2n to n
Mitosis is preceeded by a S-phase in which the amount of DNA is duplicated	Example for a diploid mother cell:	Only meiosis I is preceeded by a S-phase
Normally no pairing of homolog chromosomes	x	Complete pairing of all homolog chromosomes during prophase I
Normally no exchange of DNA (crossing-over) between chromosomes	x	At least one crossing-over per homolog pair of chromosomes
The centromeres are split during anaphase		The centromeres do not separate during anaphase I, but during anaphase II
Conservative process: the genotype of the daughter cells is identical to that of the mother cells		Meiotic products differ in their genotype from the mother cell (increase in genetic variation in the offspring)

 
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!