Unit 4 Reflection

   In my most recent lab, The Coin Sex Lab, I tested the outcome of inheritance for gender, bipolarity, colorblindness, and a dihybrid cross for eye color and hair color. The monohybrid cross for gender was based on the outcome of XX-XY, which using the punnet square you can predict that 50% will be female and 50% will be male. The colorblind portion of this test was X-linked, while the bipolarity portion was autosomal. In the dihybrid test, I flipped coins to represent the alleles of a gene where each side of the coin was a certain allele. This represents the 50-50 probability of a certain allele resulting in the recombination. In the dihybrid cross, when when two double heterozygous dihybrids where crossed, the actual results where quite different than the expected results. The expected results said that there would be 9 brown haired brown eyed, 3 brown haired blue eyed, 3 blond haired brown eyed, and 1 blond haired blue eyed. But in the actual results there where 11 brown haired brown eyed, 0 brown hair blue eyed, 4 blond hair brown eyed, and 1 blond hair blue eyed. In this experiment blue eyes, and blond hair where homozygous recessive. This difference in numbers is because the expected results are the most probable results, this however does not mean the actual results are always going to follow this. The actual traits are random, however certain combinations have a higher probability than others. This means that probability is only limited to how likely a combination is going to happen, not what is going to be the exact result.  This understanding relates to life because it can be used to predict the phenotypes of children with parents who have certain traits.

Meiosis

   This unit was about sex, including the topics of inheritance, mitosis, meiosis, and asexual vs. sexual reproduction. My most recent project which is used to explain how the probability of genetic inheritance and randomness work together, and that the probability of an offspring's traits can be known but not completely predicted. Punnet squares can be used to know the probability of both monohybrid and dihybrid crosses. Mitosis is how cells reproduce by cloning themselves, and Meiosis is the process in which a cell divides into two gametes, each with half of it's genetic code that might be used to create a new organism. Asexual reproduction is when an organism basically clones itself, creating a new organism with the same genetic code. Sexual reproduction is when an organism combines half of it's genetic code with half of another's code to create a new organism. Both of these have costs and benefits, see my blog post about this for more information. Most of this content was easy to learn, however I did not immediately understand dihybrid crosses, now I understand them.

X-linked Inheritance

   From this experience I learned the many concepts of reproduction and how they all work together. I learned how to do dihybrid punnet squares, which was new to me because all I had done before was monohybrid punnet squares.  Also I learned about the process of meiosis, which I had not known about before. X-linked recessive genes like colorblindness are interesting because they will express themselves in males more often because they only need 1 chromosome to be recessive, because there is only 1 X chromosome in males. While doing the Genetics Infographic I reviewed content I had learned earlier in the unit, and previewed content I would learn later in the unit. This was useful to help understand the topics myself and to help other people understand the topic. I want to learn more about polyhybrid crosses since I did not fully understand this concept. Besides that, all the content was easy to learn and I know much more about genetics now than I did in the beginning of the unit.

Image citations can be found at the bottom of the Genetics Infographic.