Mitosis and Meiosis Notes PDF

Brianna Stech Bio notes Mitosis notes #1 ________________ Cell cycle- consists of multiple “phases” Interphase- consists of G phase, S phase, and G2 phase * G1 phase- basic cell growth * S phase- DNA synthesis conce started, cycle is ty...

Brianna Stech Bio notes Mitosis notes #1 ________________ Cell cycle- consists of multiple “phases” Interphase- consists of G phase, S phase, and G2 phase * G1 phase- basic cell growth * S phase- DNA synthesis conce started, cycle is typically completed * G2 phase- cell prepares for mitosis M phase- known as mitosis * Consists of prophase, metaphase, anaphase, and telophase Prophase- chromosomes become thicker and become visible in microscopes * Nuclear membrane begins to disappear * Centrioles move to opposite ends of the cell * Spindles attach near the centromere Metaphase- the chromosomes line up in the middle of the cell * Spindle fibers, at each end of the poles attach to the centromere Anaphase- chromosomes pull apart and move into opposite poles * Spindle fibers pull chromosomes, centromere splits for this to occur * Anaphase ends when chromosomes stop moving Telophase- The nuclear membrane reforms and the chromosomes break apart * Spindles break apart * Nucleolus is visible * Mitosis is complete, but not cell division Cytokinesis- in animals * Occurs at the same time as telophase * Cell membrane draws toward the middle and the cell pinches into two daughter cells Cytokinesis- in plants * The cell plate forms midway between the new nuclei * The plate develops and separates the membrane and the cell wall appears in the cell plate Differentiation- specialization of cells Ex- Egg+sperm-- chromosomes-- mitosis-- separation-- human Stem cells- unspecialized cells Miosis- Mitosis- cell division * Diploid division * A set of chromosomes from both parent * Produces two identical daughter cells Notes #2 ________________ Cancer- renegade cells escaping the controls on cell division What is cancer? * A disease of mitosis, the regulation of mitosis get ignored by the cancer cells * When ignored, the single cell becomes transformed from a normal cell into a cancer cell Why does this happen? * This change from normal cell into a cancer cell happens when a DNA mutation occurs in one of several genes Tumors- How does this form? * The cancer cell proliferate to form mass of cancer cells (tumor) * As the tumor grows, it releases proteins from the cell to attract new blood vessel growth Benign- tumor cells remain at original site * Can be removed surgically or killed by radiation * Usually eliminating any further cancer development at the site Malignant- some tumor cells send out signals that tell the body to produce a new blood vessel at the tumor site * These cells have their own food, oxygen supply, and they have a way to escape to a new part of the body * Cells escape through the new blood vessel into the bloodstream * Cells that escape and get into the bloodstream, can start new tumors Metastasis- remove of the tumor * Surgery is performed to remove the tumor * Followed by radiation and chemotherapy