140 likes | 293 Views
Friday, October 18, 2013. “Experience is simply the name we give our mistakes .” ~ Oscar Wilde. S.C. Standards for Today : B-2: The student will demonstrate an understanding of the structure and function of cells and their organelles . Today’s Objectives : Uncontrollable Cell Division
E N D
Friday, October 18, 2013 “Experience is simply the name we give our mistakes.” ~ Oscar Wilde S.C. Standards for Today: B-2: The student will demonstrate an understanding of the structure and function of cells and their organelles. Today’s Objectives: • Uncontrollable Cell Division • Cancer Mini- Research Activity Reminder: Content Recovery must be completed by TODAY10/18/13. Midterm, next Thursday10/24/13. Warm Up: • What is the difference between primary and secondary succession? • True or False: Commensalism is defined as both species benefitting from the relationship.
Cell Cycle Control • Cell cycle is driven by a chemical control system • Triggers and coordinates the cell cycle • Regulated at certain checkpoints
Cell Cycle Control • 2 types of signals: • Internal signals • Cell senses presence of enzymes that were produced inside • External Signals • Cell senses chemicals that were produced outsidein other cells
Cell Cycle Control • Cells can respond to physical signals from their envt. • Examples: • Too close= stop dividing • Too much space= start division
Metaphase/Anaphase: Are all of the chrom. attatched to the spindle? Start: Is the environment favorable? G2/M:Is all the DNA replicated? Is the envt. favorable?
What happens to the cell if it is not ready for the next step? • The cell can wait until the environment is favorable • It will hold the cell at the checkpoint until the problems are solved • If all of the DNA is not copied correctly, cell cycle is held at the G2/M checkpoint until the error is corrected
Apoptosis • Programmed cell death • Suicide program is activated within an animal cell • Death is mediated by intracellular enzymes • Problems that cannot be fixed and the cell will self-destruct in for the benefit of the entire organism • Cells receive a change in signals
Mutagens • Latin for origin of change • Physical or chemical agent that changes the genetic material • Increases the frequency of mutations • Carcinogens: • Any agent, such as a chemical or form of radiation that causes cancer
Cancer • Cells ignore the normal signals that control cell division • Divide excessively • Normally: immune system realizes that the cell is damage & destroys it
Cancer • Abnormally:cell divides and each daughter cell is a cancer cell • Malignant tumor: mass of cells that invades and impairs the functions of one or more organs • Benign tumor: Mass of cells that remain at the original site
Mini-Cancer Research • You will work with one partner to research different types of cancer • You will select a cancer from the following list, based on how your stick is pulled from the bag • You will access the file from the website and submit via eBackpack