For this project, I had the privilege to study the process of Meiosis by creating a stop motion video. In order to do so, I had to dig deeper to find out what Meiosis actually is. I learned that Meiosis can also be referred to as reductional division. Meiosis is the foundation of sexual reproduction. Through two stages and multiple phases, Meiosis creates four haploid cells from one diploid cell. Each haploid cell has half the amount of genetic material as the original cell, meaning that it does not have enough chromosomes to create a new organism alone. This is why two haploid cells, one from each parent, must join together in a process called fertilization to form a diploid cell with enough genetic information to create a new organism. Meiosis is similar to Mitosis, but it only occurs in germ cells. The most common type of germ cells are gametes: sperm for males and eggs for females. Meiosis serves to create genetic variation within a species. It does so with two main events: crossing over and independent assortment. Crossing over occurs during prophase 1. When the chromosomes come close enough together, there is a chance that a chromatid from one chromosome crosses over onto the other chromosome (seen below). Now, each chromosome contains part of the other, thereby increasing genetic variation.
The other way genetic variation is achieved through Meiosis is through a process called independent assortment. This occurs when the haploid cells from the male and female combine to form a diploid cell. Each parent's slightly different traits have a random chance of being in their offspring. For example, in the picture below, the offspring has a chance of having traits from the dad, mom, or a mix of traits from both.
This genetic variation is key to the survival of a species. This is because it allows individual organisms to have certain traits that allow them to survive better, which forms the basis of natural selection and evolution. However, if just one small error occurs during Meiosis, the offspring may have significant deformities. One way Meiosis could go wrong is non-disjunction. Non-disjunction is when homologous chromosomes fail to separate into their daughter cells (seen in the picture below).
This may result in diseases such as Down syndrome, Triple-X syndrome, Klinefelter's Syndrome, and Turner's Syndrome. This is also the reason that panda bears have 42 chromosomes, while normal bears have 74. Pandas may have come into existence after a disjunction occurred during meiosis of a normal bear. The result was a odd colored bear with less chromosomes. However, this color turned out to be an advantage for Pandas because the flashy color helped them to find others to mate with and ward off dangers in their bamboo habitat. This proves that non-disjunction doesn't always result in physical ailments, but can instead aid in the process of natural selection. Sadly, now that bamboo forests are disappearing, pandas are becoming endangered because their colors are no longer an advantage to them.
The final version of our stop motion movie is below. Having had some previous knowledge of stop motion movies, this project was the most fun so far. I'm very happy with how it turned out. However, in order to improve this lesson, I would recommend giving us more time to work on our project. Doing so would allow us to make a more smooth video with more frames. It would also allow us to plan through exactly what we wanted to do, so we could avoid making silly mistakes and having to restart like my partner and I did. Other than that, this was an amazing experience and I hope Mr. Wong lets us do more projects like it!
https://www.youtube.com/watch?v=AHoBRteLK1s
Works Cited:
http://www.biology.iupui.edu/biocourses/N100/2k2humancsomaldisorders.html
E.O. wilson textbook
http://www.reddit.com/r/askscience/comments/2ommzw/how_often_are_there_genetically_identical/
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