Blog for 1/29/10

Dear Marika

The difference between mitosis and meiosis is that meiosis makes sperm cells and egg cells. Mitosis creates normal cells, like skin cells and cheek cells. They are non-sex related cells. In mitosis, you make only 2 cells, when meiosis makes 4. They all have different chromosomes. They have one kind from mom, and another from dad.

Blog for 1/25

This week, we started meiosis. Meiosis is very close to mitosos, but is very diffrent in many ways. In meiosis, you create sperm cells or egg cells. Also, the DNA in each cell meiosis makes is diffrent. The ending number of cells in meiosis is 4, unlike mitosis which ends up with only 2. Each cell made during meiosis has half the number of chromosomes as cells made during mitosis. That is because sperm cells would connect with another cell with half the number of chromosomes, from the female, and together, that would make 100% chromosomes. Mitosis creates 2 exactly the same cells. Mitosis create cells for the reason of just division, not anything to do with sex.

Blog for 1/19/10

This week, I learned a lot about mitosis and the different steps of it. A step before mitosis even begins is interphase. This phase is when the cell is normal and the DNA is still spread out. When did an activity online with the whole class, we summarized that in a whole cell, most of the cells are in the process of interphase. As an experiment, we looked at onion ring cells which had been preserved to look just as they had when they were alive. When we looked at these cells under a microscope in high power, you could see the DNA, and tell which phase it was probably in. The ones with only 1 small dot meant that the cell was in the phase of interphase. The ones with many small squiggles and looked as though they didn't want to be separated were in the phase of metaphase. We also learned about the differences between chromatids, chromosomes, and chromatin. Chromatid is the unraveled DNA. A chromosome is a single strand of a chromatin. A chromatin is in the shape of an X and is connected with a small thing called a kineticore.