Mitosis and interphase

• the cell cycle is composed of the interphase and the mitotic phase.
• what occurs during interphase?


  growth phase 1: cells grow in size, transcription for RNA occurs, protein synthesis. synthesis phase: chromosomes are unwound for DNA replication. Growth phase 2: cell growth.
• What is mitosis used for?


  growth, repair, asexual reproduction.
• prophase: nuclear envelope breaks down, spindles form, chromatin condenses into sister chromatids.
• metaphase: chromatids line up at the cell equator, spindle fibres attach to centromeres.
• anaphase: sister chromatids separate and are pulled to opposite poles of the cell by spindle fibres attatched to the centromeres.
• telophase: a new nuclear envelope forms around the two sets of chromosomes. the cell now contains two nuclei that are genetically identical.
• cytokinesis: the cytoplasm divides to produce two daughter cells with one set of chromosomes each.
• Histones: proteins that DNA is wrapped around to form chromatin.
• diploid: 2 sets of chromosomes, one from each parent.
• haploid: a cell that contains only one set of chromosomes (gamete)
• G1 checkpoint: nutrients, growth factors, DNA damage.
• G0 checkpoint: resting stage
• G2 checkpoint: cell size, DNA replication
• Metaphase checkpoint: chromosomes are attached to spindles
• Mitosis involves diploid cells making diploid cells but meiosis involves diploid cells making haploid cells.
• In mitosis the daughter cells are genetically identical to each other and the parent cells whereas in meiosis the daughter cells are genetically varied.