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Differences between Mitosis and Meiosis

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S.N.   Mitosis   Meiosis  
1.   It occurs in somatic cells and in germ cells during the multiplicative phase or gametogensis.   It occurs in reproductive cells of gonads  
2.   Mitosis completes in one sequence of stages i.e. in this cell division the cell divides once.   The whole process completes into two successive divisions i.e. cell divides twice.  
3.   In mitosis, chromosome doubling is followed by separation of daughter chromosome i.e. there is division of centromere in mitosis.   In meiosis, there is doubling of chromosomes once which is followed by two nuclear divisions, i.e. the centromere of chromosomes divides only once usually at the meiosis-II, or equational division phase.  
4.   The daughter cells formed by this division are genetically similar to mother cell. Amount of DNA is same as in mother cell.   The daughter cells formed by this division are genetically different from mother cell. Amount of DNA is half to that of mother cell.  
Prophase   Prophase  
5.   Prophase of mitosis is of short duration and is without sub stages.   The prophase I of meiosis is of longer duration and completes in the five sub stages, viz., Leptotene, zygotene, pachytene, diplotene and diakinesis.  
6.   The homologous chromosomes do not pair up with each other i.e. synapsis is absent.   In meiosis I, the homologous chromosomes form pairs during the zygotene stage and it appears as if the chromosome number has become reduced to half.  
7.   Duplication or splitting of chromosomes takes place in the early prophase.   Duplication or splitting of chromosomes takes place in the late prophase (Pachytene stage).  
8.   No chiasma formation or crossing over takes place.   chiasma formation or crossing over takes place.  
9.   The exchange of the genetic material between the homologous chromosomes does not occur.   The exchange of the genetic material between the homologous chromosomes occurs.  
Metaphase   Metaphase  
10.   Chromosomes appear double stranded i.e. the chromatids occur in the form of dyads.   Since, homologous chromosomes do not separate in prophase I, the chromosomes pairs appear in tetrad state, i.e. four stranded in metaphase-I.  
11.   The centromere of each chromosome divides into two and thus the two chromatids of the chromosome become free from each other.   Centromere of the homologous chromosomes do not divide, thus their chromatids do not become free in the metaphase-I.  
Anaphase   Anaphase  
12.   The two chromatids of each chromosome move towards the opposite poles of spindle.   In meiosis I, the two homologous chromosomes of each pair separate and move towards the opposite poles of spindle during anaphase stage.  
13.   The daughter chromosomes appear in singlet state. The separated chromosomes are two stranded but their centromere remains still in undivided state. However, the centromere is splitted into two in the metaphase II.
14.   The chromosomes are long and thin.   The chromosomes are short and thick.  
Telophase   Telophase  
15.   The telophase always occurs.   The first telophase is sometimes absent.  
16.   Number of chromosome remains same as in mother cell.   Chromosome number becomes half than the mother cell.  
Cytokinesis   Cytokinesis  
17.   Cytokinesis always occurs.   Cytokinesis-I may be absent.  
Significance   Significance  
18.   A diploid mother cell always produces two diploid cells by mitosis.   A diploid cell produces four haploid cells by meiosis.  
19.   Variations are not produced, so no role in evolution.   Variations are produced due to crossing over, so plays important role in speciation and evolution.  

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