The cell cycle and mitosis

Cells constantly reproduce exact duplicates of themselves. Why? Replacement Repair Growth

Cells must make an exact copy of their DNA DNA is the blueprint of the cell and is found in the nucleus

Cell growth and division happens in a series of recognizable steps called the Cell Cycle Rephrase: what is the cell cycle?

Cell cycle has three phases 1. Interphase Cell growth DNA replication occurs 2. Mitosis Nuclear division 2 daughter cells formed, each has identical DNA 3. Cytokinesis 2 identical cells

DNA forms chromosomes- For most of the cell’s life, DNA is arranged “loosely” in the form of chromatin During mitosis DNA condenses into chromosomes

Interphase Longest phase Cell grows Chromosomes are duplicated- each duplicate is called a sister chromatid

Prophase Nuclear envelope breaks down Sister chromatids joined at centromere Centrioles move to opposite ends and the spindle fibers form between them

Metaphase Short Spindle fibers attach to centromere Sister chromatids line up along midline

Anaphase Sister chromatids are pulled apart by the spindle fibers

Telophase Final phase of mitosis- opposite of prophase Chromatids reach opposite poles Nuclear envelope reforms Chromosomes unwind

Cytokinesis Cytoplasm division Cytokinesis differs between plants and animals- why?