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MIT student blogger Paul B. '11

Warning: Contains Biology by Paul B. '11

This entry may be unsuitable for children, liberal arts majors, and mathematicians.

As you hopefully already know, I am a sophomore in Course 20 here at MIT. Because we say everything here in numbers, Course 20 actually means that I am a biological engineering major. Moreover, even though I’ve planned on being Course 20* since before coming to MIT**, MIT students tend to all take the same core curriculum as freshmen. This not only provides all students with a common core of foundational scientific knowledge, it also prevents students from being pressured into declaring a major too early too.

But now that I’m a sophomore, I get to start taking exciting Course 20 classes!

…well, sort of.

I say “sort of” because although three of my five classes this term are recommended and required for a Course 20 degree, only one of them is, strictly speaking, Course 20.

But that’s actually part of the point of biological engineering: it is a highly interdisciplinary field, especially here at MIT; and it is continuing to evolve from the various fields that originally gave birth to it. Bioengineering is still incredibly ground-breaking, with new research pushing the limits of our knowledge every day – and that’s why I’m so excited to be part of bioengineering here at MIT, where so many fantastic discoveries have already been made.

* This is actually over-simplifying things slightly. Originally I wanted to study biomedical engineering, which tends to incorporate a lot of things from Course 2 (mechanical engineering) as well as Course 20. So for a while I contemplated declaring Course 2 or Course 2A (mechanical engineering with a particular focus; I would have chosen biomedicine, like Melis) instead of Course 20. Yet ultimately I decided that Course 20, which is just straight up pure biological engineering, was the right choice for me personally.

** For the prospective students applying, do not worry about what you list as your “intended major” on your application form. Because of MIT’s centralized, “single-door” admissions policies, all applicants are reviewed by the Admissions Office equally no matter what you put down. That question’s only purpose is to help the Admissions Office get a sense of what your passions are and how you have explored them before applying (for example, competing in science fairs, attending engineering summer camps, participating in FIRST, or doing research).

It’s also perfectly fine to put down “Undecided” if that’s what you honestly are. I know several friends who put that down on their application and got in. Don’t let anyone tell you that being unsure about your future stop you from being admitted to MIT – who really expects 17-year-olds to be 100% sure about what they want to do for the rest of their lives, anyway?

As I was saying, though, I’m taking three “Course 20” classes this term:

  • 20.110 – Thermodynamics of Biomolecular Systems
  • 5.12 – Organic Chemistry I
  • 7.03 – Genetics

20.110 and 7.03 both have homework assignments – problem sets – due tomorrow. I’ve been making good progress on them so far. But because I realized I haven’t talked about my academics all that much this term, I thought I would give you a brief insight into some of the questions that have been on my mind lately.

First, from the 7.03 problem set, Question 1:

Growth on glycerol in yeast requires a functional electron transport system. Some of the enzymes in this electron transport system are encoded in chromosomes residing in the nucleus and some in the mitochondrial DNA. This situation means that a strain unable to grow on glycerol could have a mutation in the nuclear DNA, the mitochondrial DNA, or both. For the nuclear notation, a wild type strain is GLY1+ and a strain that has a mutation in a nuclear gene preventing growth on glycerol is gly1-. For the mitochondrial genome notation a strain can be ρ+ or ρ- where the strain that is ρ+ can grow on glycerol and the strain that is ρ- can not. Thus, a wild type strain is GLY1+ ρ+ and a glycerol non-grower could be gly1- ρ+, GLY1+ ρ-, or gly1- ρ-. You have known haploid stocks of strains with these four genotypes to characterize any new strain.

When you cross a ρ- strain with a ρ+ strain the resulting diploid is ρ+.

a) You isolate a haploid strain that can not grow on glycerol and want to know what its
genotype is with respect to the nuclear GLY1 and mitochondrial ρ DNA. What
strains would you cross it by to distinguish whether its genotype is gly1- ρ+, GLY1+ ρ-, or gly1- ρ- ?

b) In a cross of gly1- ρ+ x Gly+ ρ- what would be the glycerol genotype and
phenotype of the four meiotic products?

And from the 20.110 pset, Question 3:

When raindrops fall, they are distorted slightly from a spherical shape due to drag forces on the sphere. Consider a droplet that is initially 1 mm in diameter. Its surface area is increased by a factor of 1.75 while falling. What is its change in free energy during the process (do not include the change in potential energy)? If this free energy were converted into heat, would the temperature of the drop change appreciably? The surface tension of water is γ = 72 dyne/cm and the heat capacity of water is 4.1 J/gm/K.

As you can see, problem sets are a lot different from high school homework. There are (usually) fewer problems, but they’re each individually more difficult and more likely to make you want to tear your hair out. Moreover, they generally can’t be answered just by using some formula you copy out of your chem textbook – you actually have to think outside the box and applying what you learned in lecture and from the text.

But that’s what MIT’s all about. We wouldn’t be here if it weren’t challenging.

25 responses to “Warning: Contains Biology”

  1. Sheila says:

    whoooaaa….those problems…should I be afraid of MIT? lol.

  2. anon says:

    haha, when i come home from school i am going to play with these hw questions :D

  3. Ivan says:

    @ Paul,

    Nice post, though I want to study EECS at MIT these blogs about biology make me want to at least try these classes, assuming I am able to get in.

    When will you post about your UROP research?

  4. ming says:

    20.110 pset, Question 3 is more like a physics problem than chem. But great problem, I like that.

  5. Paul says:

    @ming: 20.110 actually relies heavily on physics, math, biology, and chemistry. But some problems do tend to have more physics to them than others, and the one I posted is definitely fell into that category.

    @Sheila: Yes. Be very afraid. smile

    @deng: It depends on the class and the semester – I just happened to have a lot of classes this semester that chose to have problem sets due on Friday.

    @Ivan: I’m glad to hear that! I’m actually very interested in the applications EECS has for bioengineering, especially on the computer science side, and this is a big part of my current UROP.

    I’ve know that been promising to talk about my UROPs for a while, and I apologize for not delivering yet. I can’t say for sure when I’ll actually have time to write about my research, but trust me, I haven’t forgotten about it.

  6. Fiona says:

    Hee hee, are you posting the pset questions for ‘inspiration’? wink

  7. Paul says:

    @Fiona: Actually, no. If some of the prefrosh know how to solve these problems already, kudos to you – but I had already solved them myself by the time I posted them. smile

  8. tina says:

    sounds like fun smile

  9. Hiral says:

    I didn’t even read the full post and I’m feeling dizzy!

  10. Navdeep '13 says:

    Holy mothers, i am third!

    Although the post is superb.

  11. deng says:

    why are there generally more psets due on fridays?
    just because it’s the end of the week?

  12. Gale says:

    Oh my goodness, I understand how to do the 7.03 problem! I feel so proud of myself =D

  13. Oasis '11 says:

    The thing I find funny about biology is that you often read like a huge paragraph as intro, and then your answer turns out to be like a sentence or two.

    (or in the case of Question 1, just a few crosses)

  14. Quentin '10 says:

    …why are you posting on the blogs when you still haven’t finished all your work?

    This entry looks like it took you at /least/ 30 minutes to write. raspberry

  15. Kasey says:

    That looks like fun! I’ve been thinking about Biomedical Engineering for a while now, and I’m really interested in it.
    I’d also be interested in seeing an orgo pset, I’m taking it now, so I’d like to see how much harder it gets in college!

  16. Hiral says:

    @Quentin ’10
    Well said. grin

  17. Banerjee says:

    @ Quentin and Hiral:

    Probably because when people work non-stop, its nice to take a break and do something fun/different.

  18. deng says:

    well obviously the best time to blog is when you’re hosed
    I know most of the times when I post really long entries on my own blog are when I have essays or lab reports due :-D

  19. Oasis '11 says:

    @ Tiffany – – type 5.12 as course number.

  20. Paul says:

    Eisile, yes, please feel free to email me! I love helping prospective students learn more about MIT. And if I don’t know the answer to your question, I’ll do my best to find someone who does.

  21. Elizabeth says:

    Paul, I’m in the same boat as you were when you were in high school. I’m interested Biomedical Engineering, and so if I go to MIT I don’t know exactly what I would study…

    Right now my plan would be Course 20 with a possible minor in Biomedical Engineering, but like you said I could also do Course 2A and focus in biomedicine… Maybe I’ll come up with a couple questions and shoot you an email. Expect to hear from me soon smile

  22. Elisile says:

    Can I Email you?
    I’m an International student and I’m planning to apply for MIT.
    Everything you mentioned here is fascinating…~
    And I really like Bioengineering. Just want to find someone from the school to ask questions…

  23. Tiffany says:

    How could you not include an orgo problem?!!?! It’s the best subject in the world (at least it is for me in my school). Post one plz; I’d like to see if I could solve it.

  24. Reena says:

    EEE! I actually know how to do the second one!!!!
    (not thinking *at all* of doing anything biomedical engineering related, but am a meteorology/atmospheric physics freak)

  25. Kyle says:

    I want to go into Chemical Engineering but Biology scares me. Am I in trouble?