S phase- DNA replication Mitosis: the cell’s nucleus and nuclear material divide; includes four sub-stages. Prophase 1st and longest phase of mitosis Chromatin condenses into chromosomes (chromosomes become visible) Nuclear envelope/membrane disappears Centrioles migrate to poles Spindles are formed Metaphase Chromosomes line up in the middle of the cell Each chromosome is attached to spindles Anaphase Chromosomes are pulled apart Chromatids are pulled to opposite poles Telophase chromatids reach poles 2 new nuclei start to form Chromosomes start to unwind Spindles disappear Cytoplasm begins to divide; cell plate forms Cell Cycle Notes Steps in a cell’s life cycle which lead up to a cell dividing into two genetically identical daughter cells G0 a phase of the cell cycle where the cells no longer divide Interphase the cell grows, carries out cellular functions, and replicates its DNA. Longest phase of cell cycle G1- Cell Growth Cell increases in size. Makes new proteins and organelles S phase- DNA replication Chromosomes are copied. New DNA molecules are made G2-Final Growth Phase Shortest phase Check for mistakes in new DNA Prepare for nuclear division (mitosis) Cytokinesis cell’s cytoplasm divides, creating two new cells

Spindle – microtubule that helps separate chromosomes Key Vocabulary: Chromosome – contains genetic information (DNA) passed from one generation to the next Spindle – microtubule that helps separate chromosomes Centrioles – help to organize cell division Chromatin – protein-bound DNA within the nucleus A – Centromere: center of chromosome B – Chromatids: two identical “sister” parts of the chromosome Key Points: Cell Cycle includes: 1.Interphase (G1, S, G2) 2.Mitosis (Prophase, Metaphase, Anaphase, Telophase) 3. Cytokinesis Ends in 2 daughter cells with identical chromosomes and chromosome numbers