Jump to content
Premed 101 Forums

I came out of my biology midterm thinking I wrote a 90+ paper, I get my mark back


Recommended Posts

  • Replies 67
  • Created
  • Last Reply

The Calvin cycle actually does not occur in the dark, several aspects are dependent on light being present (I won't go into why, but you can PM me if you're interested).

 

At night, plants typically digest their starch. They use starch to store the extra glucose produced during the day. If you leave a plant in the dark for a long time, it will start to use up all of its starch stores. As a product of this, lots of carbon dioxide will be released, and this will reduce the weight of the plant.

Link to comment
Share on other sites

Please get into it. If it's because the enzymes don't function without light, yes, I learned that in high school, but that was not mentioned at ALL in lecture. You base your answers off of what is said in class. What was said in class was that the calvin cycle only needs the reactants of the light reaction to continue.

 

I wrote this as an answer to a very similar practice question that I made for myself in a plant biology course:

 

It would be incorrect to call these "dark reactions" because the reaction can occur in the light. It is also incorrect to call these reactions "light-independent" for a number of reasons. Firstly, the Calvin Cycle requires energy in the form of ATP and NADPH, which are required during the reduction and regeneration phases. These chemical energy carriers are produced during photosynthesis, which is a light-dependent process. Therefore, the Calvin Cycle cannot occur without the input of light. In addition, key enzymes of the Calvin Cycle only function while in their reduced states (ie. Rubisco, Fructose-1,6-bisphosphate phosphatase, Sedoheptulose-1,7-bisphosphate phosphatase, Ribulose-5-phosphate kinase, NADP-glyceraldehyde-3-phosphate dehydrogenase). The reducing equivalents needed to activate these enzymes come from ferredoxin, which is reduced during photosynthesis. Photosynthesis also sets up a proton gradient across the thylakoid membrane, resulting in a pH of 8 in the stroma. The enzymes of the Calvin Cycle operate optimally around this pH range. Lastly, several of these enzymes also require magnesium as a cofactor. The pumping of protons into the thylakoid lumen is also coupled to the movement of magnesium ions into the stroma. Due to all of these reasons, it would be a misnomer to refer to the Calvin Cycle as "dark reactions" or even "light-independent" reactions.

 

I think I see where your logic breaks down. You assume that the cycle needs the products of the light reaction to continue. This is true. However, you grossly overestimate the intracellular stores of ATP and NADPH. There simply isn't enough to last for a very long time. Surely they will run out quite quickly, and there's no way that they would last a few days.

Link to comment
Share on other sites

So how the hell are we supposed to know how much reactants the plant can store? How am I supposed to know if it lasts only a few hours if the faggot professor doesn't ever say it in class? All the other questions are like this.

 

I think it's fair that you should know this, but ultimately I'm not in your class and I don't know what your professor expects you to know. It may have been in the textbook as well, which is typically fair game for a midterm.

Link to comment
Share on other sites

Yeah if it was blatantly mentioned in the book it is definitely fair game to test it. :o

 

question aside the test is so difficult or poorly written the overall class (and not a small class at that) clearly is struggling. The only reason the OP did as well as they did was the amount of time they put towards it in the first place.

 

Not a fan at all of curving - but is it likely this test would be?

Link to comment
Share on other sites

Ok nice troll course, I hope it was pass fail course lol.

 

Wasn't it decided that only A-E was fair? so A-D choices are actually easier? Blasphemy for such an difficult exam!

 

Haha, no.. it wasn't. Thankfully, it was curved, which helped a lot. 85% got me an A.

 

^Source: http://premed101.com/forums/showthread.php?p=497762#post497762

 

Still a really nice message, and I'm glad to see it again

 

Great story, but I really hope it's actually true. :o

Link to comment
Share on other sites

question aside the test is so difficult or poorly written the overall class (and not a small class at that) clearly is struggling. The only reason the OP did as well as they did was the amount of time they put towards it in the first place.

 

Not a fan at all of curving - but is it likely this test would be?

 

Linear adjustment upwards of approx. 11%; after the adjustment the average was ~64. OP's mark is the mark after the adjustment.

 

Can't even argue with you FailureInLife, that was a pretty tough exam. Although the question you picked as an example didn't really reflect its difficulty lol, there were much harder ones

Link to comment
Share on other sites

i'm actually done with this biology department. you want me to talk to the professor? do you know what haffie does to you? He talks to you like you're subhuman when you're in his office questioning his questions.

 

Is he really that bad to talk to? Not saying I don't believe you, just genuinely curious. Some people I've heard from say he's not a bad guy at all when you talk to him, others have an experience like yours where they can't stand him anymore

 

The worst is when you have three options followed by two of these: A + B, B + C, A +C, all of the above, etc... :mad:

 

haha we have all kinds of multiple multiples at western as well, not all of our questions are simply ABCD

Link to comment
Share on other sites

Linear adjustment upwards of approx. 11%; after the adjustment the average was ~64. OP's mark is the mark after the adjustment.

 

Can't even argue with you FailureInLife, that was a pretty tough exam. Although the question you picked as an example didn't really reflect its difficulty lol, there were much harder ones

 

ahh ok, that makes sense. Still a weird test.

Link to comment
Share on other sites

Yep. Actually, in one course, we had scantrons from A to Z, where each question went up to G. That was ridiculous. :eek:

 

The worst is when you have three options followed by two of these: A + B, B + C, A +C, all of the above, etc... :mad:

 

Yeah, those are really annoying. Most of my multiple choice exams first and second year were like that. Plus you get the questions that sound like double negatives sometimes, that make you really read the question carefully to figure out what is going on. It actually made me feel a little sorry for the students who didn't have English as their mother tongue, as the wording of some of those multiple-option questions can also be tricky.

 

In third and fourth year, most of my exams have either been all short answer, or part short answer and part multiple choice. So no more of the full MC exams anymore. Even in large classes (400 students in physiology), the prof still had some short answer questions on the midterms, and some short and long answer on the final.

Link to comment
Share on other sites

i'm actually done with this biology department ... i have to either transfer out of this university or start a new major, because my 98%+ in computational courses and 60%s in biology courses clearly isn't working out

 

Transferring to another school over a bad midterm? really? What happened to you at your school can happen at another. There's no guarantee that it won't. Also, somewhere along the way OP, you're going to be asked why you switched, and there's no good answer because everyone was in the same boat, and getting high grades was possible.

 

All this talk about bellcurving is unproductive, and anyone pulling you into that discussion isn't really helping. You should be focusing solely on where you went wrong, and ways to do better next time. Otherwise, you won't learn anything from this and it'll happen again.

Link to comment
Share on other sites

honestly, just knowing you're going to do well, almost faith... in undergrad i honestly never really ran out of study time... and i'd often do 12 hours str8 before the exam... but when you've done this before, it's like a skinnerian reward schedule, you don't get dejected, because you know you need that full 12 hours for results, so go in blind, and give er

Link to comment
Share on other sites

There's honestly nothing to learn from this aside from the fact that I'm a bad test taker. I knew everything I needed to know, but I didn't apply my knowledge the way the professors wanted me to. Anyone know of any studying techniques that can help refine my application skills?

 

Other posters have mentioned this, but I'll state it again because it's true: TALK TO YOUR TEACHERS. Go to office hours. Go to supplemental hours.

 

Part of this is to get in the head of your teachers, to learn how they think about problems so that you can think that way as well. Most of it, however, is to see how all the fact you're learning actually fit together. Sometimes this involves getting little bits of information not emphasized or missing from lectures. Sometimes this involves just developing the real-world context so that when you have a problem like the one you stated, you can draw on that context to see if one answer makes more sense than another.

 

Lastly, talk to your fellow students. Obviously some of them - quite a few in fact - managed to get A's in this class. Learning from them is important. They can provide a lot of information and context too, and teach you some problem-solving techniques. Regardless of how fair a class is or isn't, if you're in the middle of the distribution of marks, you likely won't get the kind of grades you feel you need to get. Someone else did it, so you can't do it too - learn what they did.

Link to comment
Share on other sites

Other posters have mentioned this, but I'll state it again because it's true: TALK TO YOUR TEACHERS. Go to office hours. Go to supplemental hours.

 

Part of this is to get in the head of your teachers, to learn how they think about problems so that you can think that way as well. Most of it, however, is to see how all the fact you're learning actually fit together. Sometimes this involves getting little bits of information not emphasized or missing from lectures. Sometimes this involves just developing the real-world context so that when you have a problem like the one you stated, you can draw on that context to see if one answer makes more sense than another.

 

Yep. Even if you don't like your prof, or think they talk down to you, still, go to their office hours.

 

If you can get a hold of past exams, do so. I know sometimes exams aren't returned, so it can be hard to get copies, but if they are available, make use of them.

 

Does your university have supported learning groups or a learning commons? At Guelph, there are Supported Learning Groups for all the large first-year courses that typically give students problems. They are led by an upper-year student who did well in the intro course. They go over tips, reinforce some of the more difficult concepts, and basically help you learn the material. If your university has something similar, then make use of them!

 

The same goes for a learning commons, or whatever organizes seminars or workshops on how to learn and study effectively. Again, at Guelph, there are seminars and workshops available to help students learn how to best study for different types of courses and exams. They also have individual appointments you can make to go over problems you might be having. See if your university offers something similar. For example, one of the workshops offered is called "The art of multiple choice" and they help students learn how to effectively tackle multiple choice exams.

Link to comment
Share on other sites

We don't get any

 

But why does my brain suddenly become retarded when I'm writing the exam? I really don't understand the reason why I chose some of the answers I chose. When I look at my answers, they make no sense at all. It's almost as if I wrote the wrong exam code or something. I wasn't even nervous during the exam or anything, but I made all these mistakes... WHY?

 

Again, workshops or one-on-one meetings with learning professionals can help you identify why you make those mistakes in an exam situation, and can teach you ways to deal with it.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.


×
×
  • Create New...