Biochemical pathways of importance

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Pick the top three most important biochemical pathways to know for med school.

  • glycolysis

    Votes: 40 76.9%
  • TCA cycle

    Votes: 30 57.7%
  • electron transport chain

    Votes: 17 32.7%
  • gluconeogenesis

    Votes: 24 46.2%
  • pentose phosphate pathway

    Votes: 8 15.4%
  • glycogen synthesis/breakdown

    Votes: 14 26.9%
  • beta-oxidation of fatty acids

    Votes: 13 25.0%
  • amino acid synthesis (loads of pathways in this category)

    Votes: 11 21.2%
  • purine/pyrimidine biosynthesis

    Votes: 9 17.3%

  • Total voters
    52

strongboy2005

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How much emphasis does medical school place on memorizing biochemical pathways? Of the following pathways, which are the most important to memorize?

glycolysis
TCA cycle
electron transport chain
gluconeogenesis
pentose phosphate pathway
glycogen synthesis/breakdown
beta-oxidation of fatty acids
amino acid synthesis (loads of pathways in this category)
purine/pyrimidine biosynthesis

I ask because I'm finishing up my undergraduate biochemistry class and I want to know which pathways are the most important to remember and which pathways (if any) I could be okay forgetting. The only one I really have memorized outright so far is glycolysis (structures, enzymes, substrates, everything).

I'm attaching a poll as well. For the poll, pick the top 3 most important biochemical pathways to have memorized.
 
All of them. Know the key enzymes and steps at least.
 
All of them. Know the key enzymes and steps at least.
Well that sucks. Haha.

So, really there is no "top 3"? It's pretty unlikely I'll memorize them all before med. school, but I could memorize a few more on top of glycolysis.
 
All of them. Know the key enzymes and steps at least.

You should be familiar with all of them and how they fit together in the big picture and what happens when things go wrong. There's no need to commit each and every step to memory, but you do need to know key enzymes (rate-determining, usually), regulation (particularly key regulatory points), relationship with other pathways (especially where they are vital for a given system; for instance, consider the HMP Shunt's relationship with the oxygen-dependent myeloperoxidase system), and the most common pathologies associated with the pathways.
 
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You should be familiar with all of them and how they fit together in the big picture and what happens when things go wrong. There's no need to commit each and every step to memory, but you do need to know key enzymes (rate-determining, usually), regulation (particularly key regulatory points), relationship with other pathways (especially where they are vital for a given system; for instance, consider the HMP Shunt's relationship with the oxygen-dependent myeloperoxidase system), and the most common pathologies associated with the pathways.

👍 Yup, pretty much medical biochemistry in a nutshell.
 
You forgot some really big ones.

Urea cycle
Methionine/Folate-Ach-Homocysteine pathway.

Also lot of carbs that lead into glycolysis.
Like for sucrose and fructose.
Same for Galactose and Lactose.
As well as mannose-6-phosphate one.
Folate usage in our cells as well as Vit.B12 usage.
All of the cofactors from vitamins and other biologically active organic compounds.

Also, lot of rxns. for clinical importance. Glycogen storage dz, lysosomal storage ones, alkaptonuria, PKU, etc.

Also, know basic concepts of molecular bio. Some in more detail.
I think you have to minute details like it takes 4 phosphates to translate a codon into an amino acid. I don't think you have to know the source of the phosphates. It's either from ATP or GTP.

Basically, INTEGRATION is the key to the pathologies. It's about mechanisms. Like someone already mentioned.
 
You should know all about vitamin deficiencies and what happens when you are deficient. Also, it is a good idea to know the effects of insulin vs. glucagon, cortisol, and epi on glucose metabolism. Next, know all drug targets cold (usually rate-limiting steps).

Think of it in a pathology/pharmacology fashion and it will be a lot more interesting. I say this, because I'm studying it right now for Step 1 and I hate biochemistry.
 
You forgot some really big ones.

Urea cycle
Methionine/Folate-Ach-Homocysteine pathway.

Also lot of carbs that lead into glycolysis.
Like for sucrose and fructose.
Same for Galactose and Lactose.
As well as mannose-6-phosphate one.
Folate usage in our cells as well as Vit.B12 usage.
All of the cofactors from vitamins and other biologically active organic compounds.

Also, lot of rxns. for clinical importance. Glycogen storage dz, lysosomal storage ones, alkaptonuria, PKU, etc.

Also, know basic concepts of molecular bio. Some in more detail.
I think you have to minute details like it takes 4 phosphates to translate a codon into an amino acid. I don't think you have to know the source of the phosphates. It's either from ATP or GTP.

Basically, INTEGRATION is the key to the pathologies. It's about mechanisms. Like someone already mentioned.
Yay!!! Coming from a pre-med!
 
You have to know pretty much everything about all of them. The thing that's too bad is that biochem is probably one of the easier courses in med school, in the sense that you really don't have to think about anything--it's just pure memorization . . .

It still sucks when you're doing it the first time, though . . .
 
Yay!!! Coming from a pre-med!

Yay my arch nemesis is back. What do you want man? I don't respond to your posts. Why do you want to go back to those days? Haven't you heard enough about UNC admissions policy. Please, don't respond. I'll appreciate it. Thanks.
 
Yay my arch nemesis is back. What do you want man? I don't respond to your posts. Why do you want to go back to those days? Haven't you heard enough about UNC admissions policy. Please, don't respond. I'll appreciate it. Thanks.
k..im just saying, how do you knwo what he needs to know for medical school if you arent in there..just saying.
 
if you must memorize something just do the rate-limiting enzymes. unless you start in the fall you probably won't remember anything else useful anyway. to put it in perspective, i think the combined glycolysis, TCA, and oxphos pathways made up about one-fourth of one of my 5 biochem exams.
 
I wouldn't memorize all of those pathways (or even 3 of them.) That was the primary difference between undergraduate and Medical School Biochemistry: In undergrad, we focused on the facts of the pathway (steps, all of the enzymes, important reactions for some of the steps, etc) whereas in medical school, the focus was on the regulation of those pathways. Perfect example: In undergrad biochem, we spent little (if any) time talking about PFK2/FBPase2, whereas that bifunctional enzyme plays a critical role in the regulation of glycolysis, and a significant portion of our glycolysis lecture was spent talking about that.

On the original list, I think the amino acid synthesys pathways are the lowest yield. The important ones, you will pick up by osmosis (How you get Tyr from Phe, when you study the catabolism of Phe, and how it is disrupetd in PKU, etc.)

If there was any fundamental stuff that you were rusty on in Ugrad Biochem (AA names, abbreviations, properties, etc) you might want to brush up on that, so you are not spending valuable time to study fundamentals, but otherwise, I would relax and enjoy your summer.
 
👍 for just relaxing and enjoying. Honestly, you'll cover it in class.


👍

Chubby just has this personal hatred against me. It goes back several months. Obviously, he still is cranky about it.
 
What is he like some kind of biochem God? Relative perhaps?

chubby, as always, i'm on your side! 😀

Yup. mhmmm. Yeah. Yes.



Have you heard of goljan, my good friend!

why would a PRE-MED give two craps about goljan? Our number one priority right now is supposed to be drinking, partying, travelling, and everything in between, until medical school starts.
 
chubby, as always, i'm on your side! 😀



why would a PRE-MED give two craps about goljan? Our number one priority right now is supposed to be drinking, partying, travelling, and everything in between, until medical school starts.


I am pretty sure you do this (what I am about to say) too. It's called multi-tasking.
It's not much. Quick extraction and integration of medical facts. I mean you will learn it and even in greater detail probably in med school but it's good to have an outlook. Plus, goljan makes integration much easier with his style of presentation.
But, of course I am doing things (for enjoyment) like you stated right now. I mean......hello! It's the summer time.
 
I love SDN. Please, I need more advice about medical school biochem from people who haven't started medical school yet.

I was just thinking to myself that I should be posting advice to residents on how to succeed in residency.
 
I love SDN. Please, I need more advice about medical school biochem from people who haven't started medical school yet.

I was just thinking to myself that I should be posting advice to residents on how to succeed in residency.


double post.
 
I love SDN. Please, I need more advice about medical school biochem from people who haven't started medical school yet.

I was just thinking to myself that I should be posting advice to residents on how to succeed in residency.


did i tell the OP something that he shouldn't do. Please. Give me a break, dude!

I also post on step I thread. Do you want me to stop posting there too?
I learn from other people and tell things to other people. That's how this whole knowledge "thing" works. Reciprocity. It has nothing to do with age or status. More power to you if you want to give advice about residency to med students if you think you have a firm grasp on a subject(s). No one is stopping you.

But, I encourage you too correct me if I told him something that he doesn't need to know. Please, go ahead if necessary. That might help me too.
 
But, I encourage you too correct me if I told him something that he doesn't need to know. Please, go ahead if necessary. That might help me too.
I'm sure I'll regret feeding the troll, but basically, over half of what you listed as important was not covered, covered only briefly, or deemphasized in my Biochemistry course. I agree with the others -- wait until you take Medical Biochemistry before giving others advice about Medical Biochemistry.
 
I'm sure I'll regret feeding the troll, but basically, over half of what you listed as important was not covered, covered only briefly, or deemphasized in my Biochemistry course. I agree with the others -- wait until you take Medical Biochemistry before giving others advice about Medical Biochemistry.
I agree with this. neil100, I'm sure you're just trying to help, but it's better to let people who are in med school and have taken medical biochemistry give advice rather than base it off of your undergrad biochem experience. From all that I've read, undergrad biochem =/= medical biochem.
 
Answer: none of the above is useful. Just memorize for the 2 months you need it and try to promptly forget it afterward because it's all low yield information (unless you're gonna be a phd).

And Neil? Goljan's a pathologist, not a biochemist. chubby's after you because you're acting like a gunner, and on top of that you're giving off second hand information as if it's first-hand information. It's just annoying is all. If you wanna spend time doing that though be my guest, it doesn't get in my way.

EDIT: I'm in a snarky mood, enjoy it. For step 1 and beyond you may want to know is basic biochem surrounding, folate, B12, B6, gluconeogenesis, heme synthesis, glutathione, and very limited electron transport. And as said above, insulin/glucagon effects. then if you want really low yield stuff, you want to know some very basic biochem surrounding a few inborn error of metabolism diseases as related to fatty acids, amino acids.

And in the long run, as I said, biochem pathways are silly because you end up just learning how diseases related to biochem present, how the diagnostic testing concepts work, and maybe have one strange factoid leftover. such as how cyanide and arsenic poisoning cause damage, what's going on in G6PD hemolysis reactions, etc. But you lose your entire concepts of biochemistry pathways.
 
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Answer: none of the above is useful. Just memorize for the 2 months you need it and try to promptly forget it afterward because it's all low yield information (unless you're gonna be a phd).

And Neil? Goljan's a pathologist, not a biochemist. chubby's after you because you're acting like a gunner, and on top of that you're giving off second hand information as if it's first-hand information. It's just annoying is all. If you wanna spend time doing that though be my guest, it doesn't get in my way.

EDIT: I'm in a snarky mood, enjoy it. For step 1 and beyond you may want to know is basic biochem surrounding, folate, B12, B6, gluconeogenesis, heme synthesis, glutathione, and very limited electron transport. And as said above, insulin/glucagon effects. then if you want really low yield stuff, you want to know some very basic biochem surrounding a few inborn error of metabolism diseases as related to fatty acids, amino acids.

And in the long run, as I said, biochem pathways are silly because you end up just learning how diseases related to biochem present, how the diagnostic testing concepts work, and maybe have one strange factoid leftover. such as how cyanide and arsenic poisoning cause damage, what's going on in G6PD hemolysis reactions, etc. But you lose your entire concepts of biochemistry pathways.


Well yeah. Don't you think I would know that? I've listened to his audio and read his high yield notes.
 
👍

Chubby just has this personal hatred against me. It goes back several months. Obviously, he still is cranky about it.
??? I wanna be friends...i havent attacked you anywhere on this thread..i thought we were over the UNC foolishness?
 
Pre-studying?

only for like a month and 3 days in a week. That was back when we were still arguing about UNC policies. But, yeah we could be friends man. That sounds nice.
 
I wouldn't memorize all of those pathways (or even 3 of them.) That was the primary difference between undergraduate and Medical School Biochemistry: In undergrad, we focused on the facts of the pathway (steps, all of the enzymes, important reactions for some of the steps, etc) whereas in medical school, the focus was on the regulation of those pathways. Perfect example: In undergrad biochem, we spent little (if any) time talking about PFK2/FBPase2, whereas that bifunctional enzyme plays a critical role in the regulation of glycolysis, and a significant portion of our glycolysis lecture was spent talking about that.

On the original list, I think the amino acid synthesys pathways are the lowest yield. The important ones, you will pick up by osmosis (How you get Tyr from Phe, when you study the catabolism of Phe, and how it is disrupetd in PKU, etc.)

If there was any fundamental stuff that you were rusty on in Ugrad Biochem (AA names, abbreviations, properties, etc) you might want to brush up on that, so you are not spending valuable time to study fundamentals, but otherwise, I would relax and enjoy your summer.
Word. I agree with this post 100%.
 
I think the easiest thing to do (besides jumping on the MO that will get knocked down soon enough) is to just buy yourself your First Aid book that will become your bible, and then check the biochem section. It'll tell you EXACTLY what to focus on and what to carry forward. It won't be enough for med school biochem class but it'll help you focus your attention on what you really have to know vs. what you can just cram for the exam. You need First Aid anyway, why not buy it now and flip through it when you're smoking a stogie at poolside.
 
Every time I skim by the title of this thread I think it says "biochemical pathways of impotence" and I think decreased NO production by endothelial cells leading to decreased cGMP and inactivation of myosin phosphatase which hinders smooth muscle relaxation in the penis but that's never what it is.
 
Wow dude. At first, I thought you were just trying to be helpful. But you're really coming off as a tool. :laugh:


Wow dude..........🙄

How am I not being helpful? Your arrogance doesn't help anyone here, buddy.
I contributed my tidbit and then some people got mad. Oh well.🙄
 
hahahahahaha. this thread is awesome. 👍 chubby. and also to neil, for giving me quite a good laugh today. Go get laid man!
 
hahahahahaha. this thread is awesome. 👍 chubby. and also to neil, for giving me quite a good laugh today. Go get laid man!

Hahhaa. someone is jealous.
 
hi - i am still in undergrad, and i am registered to take biochem in the fall - however, i am required to take cell physiology which i have heard is similar. i am already taking a heavy course load including histology. how important is it that i take biochem before med school? would what i learn in cell phys be enough preparation?
 
hi - i am still in undergrad, and i am registered to take biochem in the fall - however, i am required to take cell physiology which i have heard is similar. i am already taking a heavy course load including histology. how important is it that i take biochem before med school? would what i learn in cell phys be enough preparation?
If cell phys = cell bio, they (cell bio and biochemistry) are not the same (though there are a few regions of overlap of the material.) Whether you want to torture yourself by taking an even heavier load of stuff that you will repeat in Medical School is totally up to you.
 
i just wasn't sure if taking it in college helped once you were taking it in med school.. or if you really just have to memorize it again anyway? i saw people said that college/med school stress different things anyway.. basically debating whether torture now would pay off later.
 
i just wasn't sure if taking it in college helped once you were taking it in med school.. or if you really just have to memorize it again anyway? i saw people said that college/med school stress different things anyway.. basically debating whether torture now would pay off later.

my undergrad biochem had a lot of photosynthesis and other details i didn't need to know at med school. my med school biochem class had a lot of what i'd call "cell biology" (protein synth, signaling pathways, genetics, etc.) i don't know what cell physiology is, but it sounds like it might be closer to med school biochem than undergrad biochem would be. i think you'll be fine, but make sure to check the schools you're applying to - some require biochem. if you haven't taken the MCAT yet, biochem helps for that too.
 
What on earth are you talking about? You are a soon to start medical student who is pre-studying telling other medical students what is important in a medical school class? You, and all other pre-meds who have yet to take a medical school course, have no credibility in saying what goes on in a medical school class even if you have done all of the pre-studying there is in the whole world.

Should I purchase books to learn how to fly a plane and tell pilots how to fly a plan and also tell other current and soon to be pilot students (don't have a clue what they are called) how to fly a plane?

If you are doing pre-study, more power to you. You can get honors in all of our classes if you want, but they are not as important as your clinical grades. You would be better learning how to treat a condition and how to recognize a condition than memorzie word by word all of Goljan's audios.

Um goljan doesn't do memorization. Med school does that. I am all about concepts and very little memorization. I actually hate memorization. I have seen biochem USMLE questions. So, please mind your own business. You don't have to look far. It's on the USMLE exam's website. It tells you exactly what concepts you need to be familiar with.
 
Um goljan doesn't do memorization. Med school does that. I am all about concepts and very little memorization. I actually hate memorization. I have seen biochem USMLE questions. So, please mind your own business. You don't have to look far. It's on the USMLE exam's website. It tells you exactly what concepts you need to be familiar with.

Neil, you appear to be more focused on succeeding in medical school than 90% of actual medical students. I'm kind of sad for you. You want it just a little too much, and it's very off-putting. I'm afraid you are going to find that most doctors (your professors, and future colleagues) don't care all that much about your grades. Much of med school is a personality contest. The exceptions are obviously derm, ophtho, and neurosurgery, since doctors in those fields have no personalities. If you irritate people, it will outweigh your grades big time. Think about it.
 
Um goljan doesn't do memorization. Med school does that. I am all about concepts and very little memorization. I actually hate memorization. I have seen biochem USMLE questions. So, please mind your own business. You don't have to look far. It's on the USMLE exam's website. It tells you exactly what concepts you need to be familiar with.

Do you have a picture of yourself that I can use for the "Premeds who hate premeds" facebook group?
 
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