3/17/11

The Cell Cycle

First in class, Mr. Finley told us that if we couldn't do the homework from last night because your computers wouldn't open the simulation, you can show him the homework tomorrow. Also, if you can't open the simulation, it works better on older computers.

Paramecium

Next, we discussed with our groups about how a paramecium reproduces. My group said that a paramecium is single-celled and eukaryotic, so the paramecium would go through mitosis. First, there is prophase, which is when chromatin becomes chromosomes and becomes visible, the nuclear membrane breaks down and dissolves, centrosomes become centrials which also move to opposite sides of the cell. Next, there is metaphase. Metaphase is when the centrials create spindlefibers which align the chromosomes at the center of the cell. Then, anaphase is when spindlefibers pull chromosomes to opposite sides of the cell. Lastly, telophase is when a new nucleus forms around chromosomes and the cell starts to pinch closed.

Next, we discussed how we reproduce. We need two parents and the offspring don't look exactly like the parent because it has genetic information from both parents. Also, sexual reproduction and sexual intercourse are commonly mixed up. Remember that sexual reproduction is the actual cells reproducing.

We also learned that....
-sex is just a delivery method that gets the cells where they need to be

-sperm cell- male

-egg cell- female
-other traveling cells are pollen (plants) and spores (fungus)

-sperm cells come from testicles

-egg cells come from ovaries

-zygote- combined cell

When the sperm cell finds the egg, the genetic material combines, it becomes one cell , and the cell continues to grow. When the cell combines, the new cell has 50% of each original cells chromosomes (50+50= 100%).

M.K.B. 4th blog