Daughter cells have the same number and kind of chromosomes
Increases the number of cells (growth)
Repair of damaged cells and cells that die from accidents (normal wear and tear)
Chromatin to chromosomes
Chromosomes: 2 chromatids joined by centromere
Disintegration of nuclear envelope and nucleoli
Formation of spindle fibers (visible)
MITOSIS Metaphase Chromosomes aligned at equatorial plate (Metaphase plate)
Paired centromere of each chromosome separate
Movement to opposite poles
Spindle fibers disappear
Cell plate is visible
Formation of nuclear envelope and nucleoli
Dispersal of chromosome mass
MITOSIS Telophase Cytokinesis – vesicles from golgi apparatus move along microtubules to the cell where they coalesce forming cell plate.
Extra pictures Interphase metaphase 1
condensation of chromatin;
members of each homologous pair synapse;
crossing over between synapsed pairs occurs;
Nucleolus and nuclear envelope break down ;
two centromeres of each tetrad attach to spindle fibers
Homologous chromosomes- chromosomes that exist in pairs; pair shares the same same genetic loci and centromere placement; pair also has identical gene sites (locus) along their lengths
Chromosomes have maximally shortened
Homologous pairs align at metaphase plate
single centromere holds each pair of sister chromatids together;
each dyad is pulled toward each pole;
sister chromatids arrive at the opposite poles;
each daughter cell has half the number of chromosomes;
Chromosomes condense once more (dyad)
Nucleolus and nuclear envelope disintegrates
Metaphase II Chromosomes align at metaphase plate
separated sister chromatids move toward the poles;
separated sister chromatids (chromosomes) arrive at the poles;
nuclei form around chromosomes;
after cytokinesis, four haploid gamets are formed
Both Mitosis and Meiosis are forms of cell division.
Both Mitosis and Meiosis allow for replication. Mitosis leads to cellular replication. Meiosis leads to organism replication.
Both Mitosis and Meiosis occur within the nucleus of the cell and go through the same steps known as Prophase, Metaphase, Anaphase and Telophase.
DIFFERENCES Criteria Mitosis Meiosis Type of cells Occurs in somatic cells Occurs in reproductive cells Number of division Consists of only one nuclear division Consists of two nuclear division M-I and M-II Product/ Chromosome number 2 diploid daughter cells 4 haploid daughter cells Cytokinesis Occurs only once – Telophase Occurs twice -Telophase I and II Pairing of homologues Yes No Crossing over Does not occur Mixing of chromosomes during prophase I Function Helps in growth and body repairs Helps in the sexual reproduction and regulation of chromosome number in the life cycle of sexually reproducing organism.
Prophase Involves relatively few changes. Involves a series of changes in chromosomes distinguished into 5 substages. Metaphase Chromosomes arrange along the equator. Chromosomes arrange equally on either side of the equator in metaphase-I. Centromeres in Anaphase Each centromere splits into two. Centromeres do not split in metaphase-l. Centrome- res in Metaphase Orient towards the equator while chromatids orient towards poles. Orient towards poles while chromatids orient towards the equator in metaphase-I. Telophase Results in the formation of two daughter nuclei having the same no. of chromosomes as that of parent cell. Telophase-II results in the formation of two daughter nuclei, each having half the no. of chromosomes as that of parent cell. Cytokine- sis Follows immediately after karyokinesis. May or may not occur at the end of first karyokinesis.