“The Life and Times of the Cell” Issues of Mitosis “The Life and Times of the Cell”
One more Phase – GAP 0 (G0) Some cells do not replicate their centrioles during Interphase. They lose their ability to divide They enter the Gap 0 stage Neurons of the Spinal cord / Brain cells
Plant vs Animal Plants have no centrioles but still form spindle fibers Plant cells divide from the inside out Cell Plate “Messy Metaphase”
Importance of Mitosis Method of reproduction for all single celled organisms Allows us to regenerate cells (tissue) repair cuts, bone breaks, etc. Growth – one cell to trillions
Cell Cycle Regulators Cyclins: are a family of proteins that regulate the timing of the cell cycle. Internal regulators: proteins that respond to events inside cell. Ex. Proteins are present to prevent a cell from entering the M phase until all DNA has been replicated first. External regulators: proteins that respond to events outside cell; they direct cells to speed up or slow down cell cycle. Ex. Growth factors.
Cancer Study of cancer is called Oncology. It is uncontrolled cell division. Starts with a single cell that loses its control mechanism due to a genetic mutation (mistake in DNA replication) Can be heredity based or environmental (like tobacco smoke, chemicals, etc.)
Cancer Treatment Three basic treatments: Surgery to remove cancer Radiation to kill affected cells New drugs are becoming available (Chemotherapy) It is hard to remove cancer (tumors often lack clear boundaries) Some tumors are very small and are found throughout the body (advanced stages) Radiation and chemotherapy are aimed at killing cancer cells The body then has to replace those dead cells which requires a lot of energy Therefore treatment must be balanced with overall patient health
Unfortunately due to natural selection cancer that seems to have disappeared can come back in the future in a form that is resistant to the radiation / chemotherapy Using multiple drugs can decrease the risk of relapse Multiple drugs decrease the probability of cells acquiring immunity
Cancer Video https://www.youtube.com/watch?v=SGaQ0WwZ_0I
Common Types of Cancer Breast Cancer Prostate Cancer Cervical Cancer Ovarian Cancer Penile Cancer Testicular Cancer Lung Cancer Pancreatic Cancer Skin Cancer Liver Cancer Leukemia Bone Cancer Oral Cancer Uterine Cancer Brain Cancer Colon Cancer Eye Cancer Lymphatic Cancer
The cure is out there !