Reproduction

How do organisms reproduce? This is the firsat question we got on the new unit, reproduction. Organisms reproduce through different forms. Two things that are important in reproduction for multi-cellular organisms are sperm and egg cells. Multi-cellular organisms have these cells that come together to produce off springs. Some organism like fish just let out sperm cells in the water and wait for another fish to gulp it up. Other organisms like humans go through more stuff. The male lets out sperm cells into the female then in the female the egg and sperm join together to form an offspring. Then there are some single celled organisms like paramecium and bacterium. these do not have sperms or eggs. These, and other cells, reproduce in different ways. First we started off a discussion saying that cells can't just split because they'd miss half of the dna and the organelles. So we started to think about some things that might need to happen. Another problem could also be that the new cells don't grow or aren't big enough. We believe that the cells grow both before and after splitting, thanks to Jeremy! We also believe that the dna must be copied first to make more dna and to make other organelles. Then we began to learn about mitosis. Mitosis is the process by which a eukaryotic cell seperates the chromosones in its cell nucleus into two identical sets in two nuclei. It is also the seperation of the cytoplasm. Mitosis has 4 important steps, prophase, metaphase, anaphase, and telophase. We will be learning more about this and other things the following week.