chromosome & mitosis

• A - T
• C - G
• Half gene received from each of the parents
• cell cycle include G1, S, G2, M
• G1 - cellular content (exclude chromosome) are duplicated
• S - chromosomes are duplicated
• G2 - the cell double check the duplicated chromosomes for error (making any need for repair)
• M - mitosis
• G2 is gap phase where cell prepares for division
• mitotic phase - nucleus divides into two daughter cells
• cytokinesis occur after mitosis
• mitosis:

  4)nucleus disappears5) chromosomes line up at the centre of the cell6) cell fibre pull the 2 identical arms of each chromosome part, toward opposite pole of the cell7) a new nucleus forms around each set of chromosomes
• cytokinesis - cytoplasm and cell membrane divides forming 2 identical daughter cells
• DNA replication occurs during S-phase (synthesis)
• chromosome - strips of tightly coiled DNA, 23 pairs (46 in total)
• Gene - codes for a characteristic
• DNA - molecule with a double helix shape, winds up into chromosome (approx. 2m in each cell)
• reasons of mitosis - growth, repair, replacement, development, and reproduction
• meiosis - making gametes
• cell fibres break chromosomes in half and pull them to different poles