Daily Newsletter March 6, 2012

Daily Newsletter March 6, 2012

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Today's Topic: Binary Fission
Bacteria do not undergo mitosis or meiosis. They lack a nucleus, thus there is no nuclear division.

When we have an organism that undergoes a replication event followed by cellular division, the process is called binary fission (splitting into two). The assumption is that the two daughter cells will be genetically identical (plasmids that don't replicate can weaken this assumption).

There are some questions you should consider:

1. What does a cell need to do before it can divide? (Hint: Biomass)
2. In eukaryotic cells, there is a signal that controls the cell cycle (CDK), are their signals that control bacterial division?
3. Without a nucleus, how do you move the genophore (DNA molecule) to opposite sides of the cell?
4. How long does this process take?  (Hint: Each species is different)
5. Is the time to division constant, or is it variable? Why?  (Hint: Conditions)

Whenever you come to a topic like cellular division, you need to "think like a cell".  Cells ultimately want to survive, and leave healthy daughter cells that survive.  You want to increase your population (that is the biological imperative at a cellular level).  So how do you do it, and make sure that the daughter cells are fit for survival?

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Daily Challenge: Binary Fission
Describe how a bacterium divides into two daughter cells.  Look at possible signals, environmental conditions, and even nutritional requirements that may affect the rate of division.  See if you can find one bacterium that is considered slow growing and one fast growing.  What is different about them?