Sunday, March 26, 2017

Reflection for Week of March 20-24

This week was all about getting back to basic genetic patterns (4.2 and 4.5), like Mendelian Genetics, and codominance (blood type and sickle cell disease).  We went over the basic terminology, like heterozygous, homozygous, dominant, and recessive, and began using Punnett Squares again.  Most of this was review from sophomore year, like generic monohybrid and dihybrid crosses, but some of it was new, like the way we learned to do dihybrid crosses by multiplying probabilities rather than making a four by four Punnett Square.  This new trick was SOOOOOOO incredibly useful, especially since we can now do, say, tetra-hybrid crosses (no, you don’t want to make a massive Punnett Square, as it turns out!).  We also dove back into Chi Squares, and while I still have some questions about the technical side of what exactly I’m looking at, not having taken Stats, I get the basic idea and can use them to analyze data.  Our last activity of the week was the fungus tetrad crossing over activity, and wow, fungus is weird.  I was very confused as to what I was seeing, but with some questions for Mrs. Cole, I mostly understood the strange lives of fungus and the activity made more sense.  Fungus are still weird, though.  
Overall, I feel pretty good about this week’s work.  Much of it was review, and it was good to get back to genetics, but even the new material wasn’t hard for me to understand, probably because there wasn't a ton of it for me to process.  I think I would like to take one more look at the fungus lab and really thoroughly take in the lifecycle of fungus, because it is so different from ours and I would like a more solid understanding of it.  I also need to work on my understanding of Mendel’s Laws of Segregation and Independent Assortment, as I feel a little rusty on those and where they are reflected in meiosis.  I will take another look at those, and come to Mrs. Cole with any questions I have. I would also like to better understand Chi Squares, but that is time-dependent.
Coding for genes and alleles is the purpose of DNA, so fits nicely into our information unit.  Understanding how genes are expressed is key to understanding how populations evolve and are acted upon, as was studied in Unit One, how the body synthesizes proteins, carbs, lipids, and nucleic acids, as discussed in Unit Two, and how our body is able to create and store energy, as was looked at in Unit Three.  Without genes, what would we be?  Wow, that’s a question my brain can’t even handle right now.  I’m going to stop there.  

Monday, March 20, 2017

Cancer Activity Reflection

  • Three things I learned from this activity.  
    • There isn’t a set formula for cancer.  Even within a single type of cancer, like leukemia, different genes and different numbers of genes can cause uninhibited cell growth that result in tumors.  
    • There are some chromosomes that contain more genes responsible for cancer than others.  In my groups, chromosomes 7, 9, and 17 were the main sources of cancer genes.  
    • Scientists have split cancer genes into three categories based on their functions: cell survival, cell fate, and genome maintenance.  We had discussed whether genes were oncogenes or tumor suppressors, but we had yet to learn what the functions of those two types of genes were, and how their functions would play into them causing cancer.  
  • Two things that surprised me.  
    • I was surprised that there were so many different ways to get a single type of cancer.  I had never really thought about the steps that the body goes through when it begins to have cells proliferate uncontrollably.  Once we started learning about cancers and I began to understand that multiple genes are usually involved in development of a cancer, I thought of it similar to the one-gene-one-enzyme idea: each type of cancer is produced by a single combination; there is only one way to produce each cancer type.  The truth is, there are multiple ways for a cancer to develop, different combinations that will lead to the same type of cancer.  
  • One question I still have.  
    • I am still, naturally, wondering how each of these genes operates specifically.  What part of the cell cycle do the play a part in?  Why does a mutation cause cancer?  I am curious about the pathways for each of these genes, even though it is unrealistic to learn about each of these with my lack of time.  But I might research at least a couple of them, perhaps the three I had on my leukemia card.  

Sunday, March 12, 2017

Reflection for Week of March 6-10

This week was focused on moving forward in Unit Four, specifically in cell division.  We learned the phases of the cell cycle, the phases of mitosis, the hormones and enzymes that regulate if and when a cell goes into mitosis and divides, and began looking at meiosis, the process by which gametes are formed in sexual selection (4.4).  This week was probably one of the busiest of the school year for me, and so, considering that, I think I did pretty well with the work.  For homework, we had three vodcasts in Unit 4 to complete, as well as our PCR lab write up.  This was a bit of a struggle for me, because I spent a lot of time trying to make sense of and organize all the material from the lab to ensure I included everything I needed to and made sense while doing so.  Because of this, I wasn’t able to concentrate on the vodcasts as well as I would have liked to.  Usually, if there is something in a vodcast I don’t understand, I won’t move on until I have rewatched it or searched out other material in the textbook or online to help me understand, but with my time being so limited this week, it was all I could do to get the vodcast done and make sure I understood enough to answer the WSQ questions.
We began the week by completing Vodcast 4.5 as homework.  It dealt with the phases of the cell cycle and mitosis, and reviewing the terminology associated with cell division, like chromatids vs. chromosomes, centromere, and diploid vs. haploid.  I feel pretty comfortable with all of the material in 4.5, as it is largely a review of Adv. Bio, but I will work on solidifying everything, since I didn’t get to take as much time on the vodcast as I usually like to.  Among new things mentioned in this vodcast were  1) the addition of “Prometaphase,” a little in-between phase where the chromosomes begin to migrate to the center of the cell and two complete spindles have formed, and  2) a small section of the evolution of mitosis that discusses that there are more similarities between eukaryotic and prokaryotic cells that we usually think.  I think I have a good handle on these two new additions, and find them interesting!
Our second vodcast of the week was 4.6, which dealt with regulation of the cell cycle.  This is a brand new subject for me, and so I am still feeling a bit uncertain of the specifics, such as which checkpoints are responsible for what, and which hormones and enzymes they employ.  What has helped me feel more familiar with this new material is the work we did with the HHMI packet.  I still definitely need to spend some more time straightening the specifics though.  
Our last vodcast of the week was 4.7, a review of meiosis, complete with that earworm video of the chromosomes doing do si dos.  That has literally been stuck in my head all weekend.  Anyway, Vodcast 4.7 reminded us what meiosis is, the stages it has to go through in meiosis 1 and 2, and the cell’s progression with regards to being haploid and diploid.  One part that we had gone over to an extent, but never this specifically, was how many different gamete combinations are possible.  Seeing those numbers was insane, and really made it sink in how incredible meiosis is.  I mostly understand everything to do with meiosis when I’m looking at the information, with a few questions on the whole haploid-diploid piece, but I definitely need to spend more time so that I can remember things without having to look at the paper.  I think I should be good by simply watching the vodcast again, but if that doesn’t do it, I’ll see if there are any good Khan Academy videos or other online resources, or, of course, ask Mrs. Cole.  
Cell division is imperative for life to sustain itself as an individual organism and as a species, so our work this week was crucial to our understanding of biology.  Organisms need to heal and grow, so mitosis is important to the survival of individuals, which is important to the survival of populations.  Regulating mitosis can mean life or death, because of the mutations that can be passed down affecting tumor suppressors and/or proto-oncogenes.  Meiosis is how sexually reproducing organisms are able to continue their lineage and sustain a population or species, and is the reason that we sexually reproducing organisms are all so different.  Without these processes, regulated by enzymes and hormones, we wouldn’t have the organisms we have today, nor the variation that is present in them, allowing mechanisms of evolution to act upon populations and shape them.  

Sunday, March 5, 2017

Reflection for Week of February 27 to March 3

Ok, so this week, things are going to be a bit shorter, as I am feeling rather burned out and like my brain is slowly dissolving inside my head.  Why isn’t it still vacation?  
I think I did pretty well with the work this week.  Monday we discoed Vodcast 4.4 on viruses (Domain 4.3), which I feel like I have a pretty good handle on given that I accidentally studied them for the quiz on Friday.  There are still a couple of questions I have, but nothing major.  For example, I really want to know how viroids causes disease, but, as it turns out, biologists don’t know that for sure yet (or even close to for sure, since you don’t ever really know anything “for sure” in bio).  
The rest of the week was spent on the lab (Domain 4.1, and, more importantly, my favorite part of the week!), which I feel like I understand the process of well, having completed the online lab, read the prelab thoroughly, and done the lab.  What I’m not so sure about is the whole database analyzation piece, but I’m sure I’ll have a better idea after talking to Mrs. Cole.
On Friday we had a quiz, and, after studying for it, I feel like I have a pretty good handle on the biotech tools, applications, and ethics, which I was feeling overwhelmed about the last time I wrote a reflection.  The ethics part is a difficult one, because it is personal, and I am someone who likes to take my time processing information and exploring different beliefs to understand what I myself believe.
I think I can definitely improve when it comes to understanding the analyzation part of the lab, having missed Thursday.  I feel overwhelmed right now, and am unsure how I am going to finish it by Wednesday. But I will keep working steadily and see where that gets me.
The lab largely had to do with PCR and electrophoresis, two common tools of biotech, and fits very neatly into the curriculum.  We learned about biotech tools leading up to vacation, and, in order to understand how these biotech tool work, one must understand how certain aspects of biology, like DNA replication in the case of PCR, and restriction enzymes and DNA structure in the case of electrophoresis.