Biol 241 homework
Professor: Greg Crowther
1. Compare and contrast the reasons cell division is important for unicellular and multicellular organisms. Cell division is the method in which single celled organisms reproduce. Cell division allows multi-cellular to grow and repair dead or damaged cells
2. Provide an example of why cell division remains important to an adult organism even after it isfully developed. Some cells divide to heal wounds such as cuts or broken bones.
3. What is the role of growth factors? Growth factors send molecular signals that tell cells to divide.
4. Cells divide, differentiate, or die. What is differentiation? Differentiation is when a cell stops dividing to perform a special function or to change shape.
5. What is apoptosis? Explain its purpose. Apoptosis is a process that eliminates unnecessary cells during development and destroys damage or unhealthy cell in a mature organism.
6. Organisms maintain the right number of cells by regulating the cell cycle. What are “cell cycle regulators”? Cell cycle regulators are molecular signals that stimulate or stop cell division, tell cells to differentiate, or cause cell death.
7. Watch the video clip of cell division in the small intestine. Name the general location along the villus where the following processes occur:
Cell Division: _The crypt
Cell Differentiation: _The lumen
Apoptosis: _The top of the villus 8. Name one harmless result of too little cell division. Hair loss is the result of too little cell division
9. Name one harmless result of too much cell division. Warts can be caused by too much cell division
10. List, in order, the four events we collectively call the “cell cycle.” Next to each event, write the correlating cell cycle phase name.
a. _G1 phase
b. _S phase
c. _G2 phase
d. _M phase
11. In general, what is the purpose of a checkpoint in the cell cycle? The checkpoints in the cell cycle allow the cell to appraise