Archives: Fairview Advantage

Cell Signaling Pathways

 

The links attached are to the two claymation videos we created on cell signaling in class.

G-Protein Coupled Receptors

Receptor Tyrosine Kinases

Questions:

  1. How are these two systems similar? Consider both structural similarities and similarities in how the systems function.
    • Both of these systems have plasma membrane receptors. In both pathways, a signal begins to be sent as a signal molecule binds to a receptor within the cell’s membrane. They are also similar in the ways they handle Ca+ (calcium) ions. In both systems, the second messenger (IP3) diffuses through the cytosol of the cell and binds with an IP3-gated calcium channel in the ER (endoplasmic reticulum). The Ca+ ions will then move out of the ER, down their concentration gradient, raising the Ca+ concentration in the cytosol. The ions then activate the next protein in the pathway. This process occurs in both cells.
  2. How are these two systems different? Consider both structural differences and differences in how the systems function.
    • Their overall processes of cell signaling are different. They also have different amounts of receptor proteins in a pathway. G-Protein coupled receptors are visually much more simple, whereas tyrosine kinase receptors have bits of tyrosine attached on one side. Each process will signal for different things to occur as well.
  3. Both systems can generate elaborate multistep signal transduction pathways. These pathways can greatly amplify the cell’s response to a signal; the more steps in a pathway, the greater the amplification of the signal. Explain how this amplification can occur.
    •  The example I will use here is the breakdown of glycogen by epinephrine. This amplification occurs as the hormone epinephrine acts through the G-Protein coupled receptor, activating a succession of relay molecules. These include cAMP and two protein kinases. The final protein in the chain is activated by the enzyme glycogen phosphorylase. This enzyme uses an inorganic phosphate molecule to release the monomer glucose from its polymer, glycogen. These are released in the form of glucose-1-phosphate. The hormonal signal is then amplified because the one receptor can activate a hundred molecules of a G-Protein. Each enzyme can act on many substrate molecules.

11.1: Test Your Understanding

Humans have the ability to detect and recognize many different aromatic chemicals by smell. Many of these chemicals are present in concentrations less than 1ppm (part per million) in the air. For example, the majority of humans can detect and recognize chlorine at a concentration of about 0.3ppm .

a. What characteristics of olfactory (smell) receptors would you look for on purpose to explain this ability?

  •   One should look for a longer signal-transduction pathway. With more steps, more enzymes can pass a signal to even more substrate molecules. This means even a small concentration of an aroma will set off a signal, and it will be passed along quickly enough that the small concentration can be detected strongly. The amplification must be very high for one to be able to recognize the scent of something in such a small concentration with ease.

b. Dogs are known to have a much better sense of smell than humans. Given this, what differences may exist in their olfactory system (as compared to humans)?

  • They likely have even more pathways or longer pathways for signal transduction. Aromatic chemicals can be detected very easily by dogs, therefore the amplification of the cell’s response to these signals is greater than that of humans. So, they must have a greater amount of signal transduction pathways or longer signal transduction pathways.
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Related Rates Problem

p.206, problem 15

A spherical Tootsie Roll pop you are sucking on is giving up volume at a steady rate of 0.08mL/min . How fast will the radius be decreasing when the Tootsie Roll pop is 20mm across?

Assume that the rate will be negative, since the values (dV/dt) will be decreasing

dV = 0.08mL/min

0.08mL = ?mm

when 1mL = 10mm so 0.08 X 10 = 0.8mm

dV = 0.8mm/min

solve for dr/dt

when d = 20mm, r = 10mm

V = (4/3)πr³

  • step one: take the derivative of the volume formula

dV/dt = 4πr²(dr/dt)

  • step two: plug in known values

0.8 = 4π(10)²(dr/dt)

  • step three: solve for dr/dt

0.8 = 4(100)π(dr/dt)

0.8 = 400π(dr/dt)

0.002π = dr/dt

dr/dt = 0.00628mm/min

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AP Biology – Butterfly Lab

For this butterfly lab, we isolated two painted lady butterfly larvae to represent primary consumers. The purpose of the experiment was to determine the efficiency by which the larvae could incorporate the food (in this case, representing primary producers) into their own biomass. We took two plastic cups. Both contained food medium. One only contained the food medium, and the other had the food medium as well as the butterfly larvae. We measured the mass of each cup every few days. Each day we calculated the daily mass loss of each cup. This helped to eventually calculate the mass of the butterfly chrysalises, which in turn allowed us to determine the efficiency by which the larvae incorporated the food medium into its own biomass. Our data led us to the conclusion that the butterfly larvae incorporated food medium into their own biomass with 24% efficiency. Typically, primary consumers can only incorporate food into biomass with 10% efficiency. We worked with an extremely small data sample, only having two larvae, so that could skew the results. Perhaps with a larger data sample, our results would have been more accurate. We are currently in the unit of chapters 51-55 in class. This lab relates to what we’ve been learning in class because it relates to ecology, which is the study of living things and their interactions with one another and their environment, as well as how organisms and their environments change over time.

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Atomic Bomb Debate Reflection

I learned that in general, there were many different factors impacting the decision to drop the bomb. The US had to consider how much the cost of human lives were truly worth, as well as how quickly they wanted the fight with Japan to end once and for all. The cohesive purpose of the bomb was to end the war, thus people were not concerned with the fact that it could start another war or it could absolutely devastate the targeted cities and their populations. I do understand why the dropping of the atomic bombs is such a debated topic, however I find it necessary to ultimately take a side. Although it can be debated as to whether or not the dropping of the bombs was truly the right decision, the US was right to drop the atomic bombs because it would have the least loss of American lives, and it was the quickest manner by which to end the war between the US and Japan.

The decision President Truman made is unfair to be judged, because there was great pressure on him to make a decision that would change everyone’s lives.  He was very aware of the trauma the bombs would cause, at least on a destruction basis. He had no idea how many Japanese and other lives it would cost. In order to carry out his duty to protect the people of the US as a whole, he had to drop the bomb, therefore causing damage. Truman had to be a strong leader, which means he had a responsibility to make difficult decisions in difficult times. For a person today to be able to judge the decision Truman made, they would have to have been in his shoes. They would have to understand the true pressure that Truman was dealing with. Someone would have to understand where he held governmental power and had what was best for the US without knowing the full extent of the outcome. He dropped the bomb for what he believed would be the best for the majority of people both in general and within his own country. The repercussions were not something he had time to completely consider, because he had very little time to make such a poignant decision.

All is fair in love and war, at least that’s what the saying states. In any case, although all is fair in love and war, a decision is not necessarily morally fair. It was indeed a fair decision to make, the decision of dropping the atomic bombs. It did however paint a very poor picture of the US by their treatment of others in wartime. It showed that the US was willing to make difficult decisions, even if they had to go against what is morally correct to do so. It doesn’t matter who the bomb is targeted at for the decision to be fair or unfair. If a were to drop on an American city, the only true difference is then the location. A similar damage would have occurred. I would react just the people of Hiroshima and Nagasaki had. In a word, panic. In the event of a parallel situation, where instead Japan dropped bombs on America, it would not change the fact that we were a part of a war, and it would not change the fact that the decision was fair.

 

Debate Ballot:

Topic: The Atomic Bomb

Winner: Pro

My Team: Pro

Comments: We won because our points were strong and well backed up with facts rather than opinions and what ifs. Our arguments against the con teams’s points were valid and well thought-out. We argued against their weak moral stance with facts, quotes, and military reasons that cannot be argued against with mere morals. Morals are purely subjective, whereas facts are objective. Morals may differ, but facts are always facts. An example would be that the bombing had prevented more overall lives being lost than other options, like invading Japan as a whole. If the US had invaded Japan as a whole, the entire country would have suffered, rather than two cities. In the end, our pro team had much stronger arguments.

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Le Project de Vêtements et Réflexion

 

For this project, we did many things well and some other things poorly. We worked very hard as a group to create a script that expressed all of the things we learned throughout this unit. We had to do a lot of problem solving, including figuring out when we could work on our project, finding props for the video, finding time where we could all meet up to film, and more. It took a lot of communication to make the project go as well as it did. In the future, we should work a bit harder to memorize the entire script rather than memorizing in chunks. The video would’ve been much smoother if we had done it in one take. As a process, we spent a few class periods working on writing the script, as well as writing a bit of it outside of class. We also spent time out of class to practice and film our final video. Overall, this project went very well.

 

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Poetry Project Reflection

In general, I’m quite proud of my final product. I put a lot of effort into all three of my poems, and I spent a lot of time practicing for the presentation of our poems. If anything, I’d try to improve on the presentation, if I could. It was a little rough, so if I could redo it, I’d make it better. In general though, I feel like my final product was pretty good.

 

The most helpful step was probably the peer review, because I got to see different mistakes I made and how I could improve my poems in general. The least helpful step was definitely when we had to analyze poems. I’ve never seen poetry as a thing that needs to be picked apart for themes and the like, so delving into it really wasn’t all that fun in the first place. Additionally, we’ve been doing poetry units for as long as I can remember, so I’m sure everyone already knows how to structure a poem. I really don’t think that analyzing poetry helped me to create my own, but that’s only because I already write poetry as a hobby. I already have my own writing style, my own ideas, and all of that. Analyzing poems was kind of repetitive.

 

One part of the Fairview Advantage I used was collaborate. I worked with multiple of my classmates to ensure that my poems were as good as they could be, and that everything I had in them made sense. A second part of the Fairview Advantage I used was communicate. Me and my peer review partner, as well as some friends I asked to review my work, had to communicate back and forth quite a bit so we could all make sure that our work was our best. A third part of the Fairview Advantage I used was create. For this project, I worked very hard to create a set of original poems that actually meant something. While many of the class poems described things like summer or holidays, mine described actual things that have happened to me, and have a much deeper meaning than simply looking forward to vacation. A fourth, and final, part of the Fairview Advantage I used was reflect. This is because throughout the project, we have all had the chance to reflect on our work.

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Literary Analysis Essay

I feel like the final products were useful. It was quite the learning experience to delve into the text of the Odyssey and analyze it for Greek values to write an essay on. The Socratic Seminar was another useful learning experience that gave us a deeper understanding of the Odyssey. I am definitely proud of the work I did. I wrote a lot of in-depth questions, and my essay was quite thorough. I feel like the outline and the thesis development steps were pretty useless. It’s a bit of a waste of time to write out your entire essay just to copy paste it over to another document because there’s no real issues with it. The quote journal/critical reading journal was probably the most helpful because it gave me good information and quotes to use as a part of my essay. We really only had to “create” a complete essay that demonstrates the knowledge of what we read. We also had to create a thesis and an outline for our essay. This helped us to “create” our final product.

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Textual Analysis Project Reflection

 

I am very proud of the work I have done. I put a lot of effort into all of my paragraphs, and my presentation as well. I spent a lot of time making sure everything went together. If anything, my paragraphs could have been a little more detailed. Overall, however, I think I did a good job.

 

Personally, I think the outline steps were pretty useless. It’s both annoying and repetitive to have to put your entire work into an outline, and then copy it into the actual turn in spot. It would be much easier to just write, rather than worry about all the different steps in the outline. Additionally, they don’t really do much in the scheme of things. Outlines are much more work than necessary for any writing task.

 

I had to investigate different articles in order to write my nonfiction paragraph. I also investigated a book, To Kill A Mockingbird, in order to write my literature paragraph. I investigated my community in Fairview Park to write my physical space paragraph. I used all three of these, as well as previous knowledge of privilege to create my presentation. Investigation played a large role in this project.

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