STAGES OF MITOSIS (FINAL)

• Mitosis refers to how a cell divides to produce new cells. Only somatic cells (also known as body cells) undergo mitosis.
• A cell will only begin mitosis if the conditions are correct and favorable for cell division.
• M Phase: The cell undergoes mitosis if it is a somatic cell or meiosis if it is a sex cell. It allows the cell to divide and produce new cells.
• Preparing for Mitosis: The synthesis phase involves the duplication of the cell’s DNA.
• DNA in interphase is found in the form of chromatin which condenses during mitosis. Each chromosome is made up of two sister chromatids.
• The human genome has 23 pairs of chromosomes for a total of 46 chromosomes in each cell. 23 is the haploid number whereas 46 is the diploid number.
• Haploid is often represented as n while diploid is 2n.
• The number of sets of chromosomes that a cell or an organism has is known as ploidy.
• Prophase: The chromatin condense into chromosomes; The nucleolus disintegrates; The mitotic spindle starts to form.
• Prometaphase: It begins after the nuclear envelope breaks down; The centrosomes move to opposite poles; The kinetochores found at the centromeres become apparent.
• Metaphase: The microtubules of the mitotic spindle attach and interact with the kinetochores of the chromosomes; The chromosomes align at the center of the cell, in the metaphase plate.
• Anaphase: The mitotic spindle pulls and separates the sister chromatids apart; The chromatids, now called daughter chromatids, are then pulled toward the opposite poles.
• Telophase & Cytokinesis: Daughter chromatids decondense; In animals, the boundary of the new cells is known as the cleavage furrow; In plants, it is known as the cell plate.
• Ploidy in Mitosis: The number of chromosomes before and after mitosis.