1. How does meiosis differ from mitosis? What is the ploidy number of the products in both processes?
2. What is non disjunction? Give an example.
3. Compare contrast asexual vs sexual reproduction. Describe pros and cons of each.
4. Describe what you learned in class on Thursday either about Molly or about chimeras.
This week in AP Bio we covered meiosis and mitosis. Both are ways for a cell to divide, the easiest way for me to remember the difference is that meiosis ends with 4 new cells and mitosis only ends with 2. Study tip (the “t” in mitosis stands for 2). We discussed how mitosis is the more efficient process because it takes much less energy to divide the cells.
Non dis junction is the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually resulting in an abnormal distribution of chromosomes in the daughter nuclei. One example of this is down syndrome, when the chromosomes divide unevenly.
Asexual reproduction doesn’t require sex, so therefor gender isn’t really necessary. It is good because mates aren’t needed, so the organism doesn’t need to waste time or energy searching for a mate. The down side of Asexual reproduction is that there is no difference, they are all exact copies. If the mother is easily killed by a bacteria or a virus, the offspring will most likely be killed as well. Sexual reproduction is far better because it provides variation which is important to survival. With sexual reproduction there are almost no limits to the different combinations that make up the person, which can help people be immune to the same virus that killed a person living right along side them.
Learning about Molly was a pretty cool topic, it is still pretty confusing to me how exactly it worked, but here is what I know: Molly had a hereditary disease, she needed a bone marrow transplant, and the parents wanted to have another child to treat their daughter. Basically it is impossible to find a random donor who would have the same cell protein as their daughter Molly. The solution that they came up with was to have another child to help treat Molly, the issue was that they didn’t want to pass the disease to a second child. They ended up having a “test tube baby” and made sure that the disease could not be present in the new baby. The chances weren’t great, but they also weren’t impossible. They ended up successfully having a baby with the matching genes of her sister and they were able to transplant and help Molly to survive for a little bit longer.