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Biochemistry Research Issues

  1. Dec 18, 2017 #1
    So I picked up this book (Lehninger) for being too expensive, because obviously the more pricey the book is, the better it's quality in learning... stuff... and content... it probably cures cancer, who knows?

    Anyhow, so Im reading through the book and I come across a passage I don't fully understand (Shocking!), well... It depends: Sometimes the passage isn't clear enough about an ambiguous subject matter, and the issue is usually cleared up in the next few sections, however then comes the occasion in which I don't have a clue what the thingymabob is trying to Ar-ti-cu-late.

    Afterwards Im struck with the exercises. How the heck am I supposed to check if my answers are correct? It's not like I have a Biochemistry professor who could help. So why bother doing any exercises, if nothing changes if I do them or not. If they're correct, that's cool. If not, how cruel, either way I won't know until someone comes along to give concise answers.

    My questions-

    1) - Why bother doing exercises if answers aren't provided, and I have no means of correcting myself?

    2) - Who's the genius who charges 400$ for a hardcover textbook, without adding another few pages to... oh I dont know...... GIVE ANSWERS?!

    3) - Is a career in biochemistry worth pursuing? Im technically applying in.. "pre-med", but I'm reconsidering medicine after I found out about serious corruption. My father wants me to be a doctor like he was, but I'm just not sure anymore... It's not like the work load is too difficult, just that I'd be more happy as a scientist than a civil servant.
  2. jcsd
  3. Dec 18, 2017 #2

    jim mcnamara

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    Staff: Mentor

    There are multiple issues here, thread moved to academic guidance.

    I would guess you would fare better taking a class. Biochemistry presumes a lot of background just like mathematics - Trivial example: It is nearly impossible to learn calculus if you do not understand multiplication. In a class you have someone to ask: tutors, lab assistants, professors.

    So I am guessing: you may be missing undergraduate chemistry and organic chemistry. But I do agree that not having answers is a major stumbling block to self-study. Did you contact the publisher to see if one exists - sometimes called something like a 'teacher's copy' of the book also may exist.
  4. Dec 18, 2017 #3


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    1 & 2: I suspect you already know the answer here and are just venting. That's fine. But the fact of the matter is that most textbooks are written either to be course material, or to serve as references for people who have already taken the courses. The percentage of people who buy textbooks to learn the material independently is usually quite small. In many cases, the author will also provide a separate solution manual for the textbook, but sometimes the sale of these are restricted to people who are verified as teaching the course.

    3: No one can really tell you if a career in biochemistry is worth pursuing or not. Like many STEM fields, it's important that you learn what the non-academic job market is like, because I suspect that much like in physics, there are a lot more PhD graduates than there are tenured positions available. One thing to keep in mind with medicine though is that once you're in, you have a lot of options available to you. You don't have to become a family physician. You could, for example become a researcher and go the MD/PhD route.
  5. Dec 18, 2017 #4
    It's difficult to explain without using a specific example, so lets take the chapter that covers enzymes as an extremely basic example: When I first read the chapter, it basically gave the implication that enzymes are capable of doing both the reverse reactions at the same time as the forward reaction. This confused me at first- What good is the functionality of an enzyme if it basically does nothing but speed up both reactions resulting in a fixed equilibrium?

    Now of course I rationalized it after looking further into it, but it seems as though the writer failed to communicate some essential details, or at least didn't provide the right details at the right time. If I could go back and re-write some aspect of the book to make it more clear, I would want to.

    And Im taking care of chemistry on my own fine (for now, at least anyways), and I don't see how this translates directly to biochem. I mean... sure you need to know the properties of certain lipids, etc, but usually the biochem book would explain the minimum and move on, whereas chemistry would focus on specifics. And at least in chemistry, the thinking is usually straightforward. But I can see why certain biology books fail to communicate otherwise simple details.

    Lehninger is an undergrad freshman book, so I don't see why it would have to delve too deep into organic chem early on. Biochemistry, from what I've seen so far, deals many with focusing on the chemistry of biology, and chemicals transformations/quantifying them, rather than focusing on long chains of carbon. I mean the way you would talk about Alkenes, Alkanes, and Alkynes is very different from the way you would talk about polypeptides and polysaccharides-

    Mainly that the former requires a lot of complex nomenclature and naming, while the latter is more linear and straightforward (Idk, it's alot easier to understand gene expression on a biochem level than it is to understand what the heck a (345elephante-super-carboxyl-renegade-star-destroyer-Alpha-edition-super134-Sulfhydrl-123bis-bis-bis-bis-tris-quadris-phospho-tomato-Iodide) group is. Guess I suck at chemistry because obviously naming the chemicals is more important than understanding what they do.
  6. Dec 18, 2017 #5

    jim mcnamara

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    Hmm. First off the book you cite does not appear in any of the lists of university's lists of suggested biochem texts that I googled - 5 or 6 of them.

    Also, When I took bio chem a long time ago, the departmental requirements were specific:
    2 semesters of freshman chemistry,
    2 semesters of organic chemistry
    some other Biology courses like physiology of plants/animals, plus math - analysis i & ii

    It was a 400 level course with defined prerequisites. (senior or graduate credit). So that does not mean that what you indicated is wrong, just that it sounds not quite right to me. More correctly I cannot help because I cannot quite get what would be in a freshman biochem text.

    Also try this solutions website for teachers: https://www.studocu.com
  7. Dec 19, 2017 #6


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    Your first reading was correct. Enzymes basically only change the kinetics of the reactions:
    That said, I don't know the book by Lehninger, and I haven't opened any biochemistry textbook in a very long time. But generally speaking, textbooks vary a lot in their approach, the depth of the material covered, and the assumed previous knowledge. Also, different readers have different needs and different preferences. If you have access to a well-furnished library, the best is to thumb through the available books on a given topic and try and find the one that best suits you and your background. This is what I do when I want to learn about a new topic. Usually, after a few minutes I know if a book is for me or not.

    Maybe you can skip the organic chemistry parts? The author is probably assuming no prior knowledge of the subject and feels that some understanding of the basics of to bonding of carbon atoms is important to understanding biochemistry at a more fundamental level than just learning the Krebs cycle by heart.

    While it may seem that nomenclature is like sorting a stamp collection, recognizing functional groups and their organization is an important step in understanding what can happen chemically to a molecule.
  8. Dec 19, 2017 #7
    Again, I used that only as an example for simplicity's sake. For the most part, it's rare that I come across anything substantial that I don't understand completely. Perhaps I should've been more clear: Upon my initial reading, I was under the silly impression that the both reactions were catalyzed, AT THE SAME RATE. I understood how enzymes increased the kinetics, but what I didn't understand was why reactions would only favor the "forward" reaction, due to the wording of the thingy. After all, what use would enzymes be if they catalyzed the reverse reaction as much as it did the forward reaction: You could convert Glucose into Pyruvate, but what'd be the point if the pyruvate would just be turned back immediately?

    The point is, the book didn't emphasize enough about the differences in energy between the two molecules, both in chemical potential energy, and activation energy. (Why am I ranting on about this..?) Next question~

    It's not that I take issue with the nomenclature... entirely. I just feel that, especially at this level (which might be different than the one you're might've been taught at) It might be a bit... superfluous? The problem isn't with recognizing functional groups, but I have bad memories about having to be able to recall the literal naming system made for chains of carbons 5+ Carbon atoms long. In the end it just felt like a waste of time, considering that without consistent practice, I've forgotten the basic principles. By the way, this is what I'm talking about:


    For example: (4-bromo-1-methoxy-2-nitrobenzene). As opposed to what? (2-nitrobenzene-4-bromo-1-methoxy)? What difference does the ordering of the words make?!

    Meh, this is just venting. It doesn't really help improve the circumstances...

    I appreciate the help you've provided, thanks~
  9. Dec 19, 2017 #8

    jim mcnamara

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    I think we have done what we can do in the thread. Thanks to everyone for participating. Thread closed.
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