So who's good at bio? help please

[SyNTHaX ERRoR]

I'm having trouble understanding and remembering negative feedback when pertaining to the endocrine system.. Can anybody recommend any good sources to read or anything that has helped them get more of a clearer perspective on it? I'm new to the forums so if this is on another thread somewhere I apologize because i'm working right now and really didn't do much searching.

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[latrala2300]

my apologies if this link makes me appear glib, but wiki tied several things together (negative feedback outside of the biological field..gasp). additionally, you may find the visual to be great in remembering negative feedback (though it's really a concept--not something easily memorized)

http://en.wikipedia.org/wiki/Negative_feedback

 

[muhali3]

Negative feedback is just knowing that the product of a multi-step reaction will inhibit the production of itself by binding to the molecule that triggers the reaction.

 

[SyNTHaX ERRoR]

my apologies if this link makes me appear glib, but wiki tied several things together (negative feedback outside of the biological field..gasp). additionally, you may find the visual to be great in remembering negative feedback (though it's really a concept--not something easily memorized)

http://en.wikipedia.org/wiki/Negative_feedback

Thanks for responding, I looked at that and reviewed it and it does help a bit. But heres the problem I'm having a bit of trouble on:

which of the following side effects might be experienced by a ptient who is administered a dose of thyroxine?

A. An increase in endogenous TSH production
B. A decrease in endogenous TSH production
C. An increase in endogenous thyroxine
D. A decrease in endogenous parathyroid hormone production

The answer is listed as "B" and after reviewing why it makes sense but i'm just having trouble remember why. Does that make sense?

 

[SyNTHaX ERRoR]

Negative feedback is just knowing that the product of a multi-step reaction will inhibit the production of itself by binding to the molecule that triggers the reaction.

ok well put, perhaps my problem is distinguishing when something will have a negative feedback vs positive. If I know something will have a negative feedback I can easily solve the problem but when i don't and positve feedback and negative feedback are thrown into multiple choice I always guess wrong. Only in the area of the endocrine system for some reason.. maybe i'm overthinking things.

 

[Salient]

Thanks for responding, I looked at that and reviewed it and it does help a bit. But heres the problem I'm having a bit of trouble on:

which of the following side effects might be experienced by a ptient who is administered a dose of thyroxine?

A. An increase in endogenous TSH production
B. A decrease in endogenous TSH production
C. An increase in endogenous thyroxine
D. A decrease in endogenous parathyroid hormone production

The answer is listed as "B" and after reviewing why it makes sense but i'm just having trouble remember why. Does that make sense?

Remember that your body tries to keep everything in relative balance. Thyroxine is a thyroid hormone. TSH is thyroid stimulating hormone (causes your thyroid to release things like thyroxine).

So if you artificially give yourself a bunch of thyroxine, your body is going to stop producing it... i.e. it will stop producing TSH.

If it was positive feedback, thyroxine would stimulate TSH which would stimulate thyroxine which would stimulate TSH which would... ...put you in a world of hurt. See why negative feedback has to be at work here?

 

[SyNTHaX ERRoR]

Remember that your body tries to keep everything in relative balance. Thyroxine is a thyroid hormone. TSH is thyroid stimulating hormone (causes your thyroid to release things like thyroxine).

So if you artificially give yourself a bunch of thyroxine, your body is going to stop producing it... i.e. it will stop producing TSH.

If it was positive feedback, thyroxine would stimulate TSH which would stimulate thyroxine which would stimulate TSH which would... ...put you in a world of hurt. See why negative feedback has to be at work here?

Now i see perfectly. That is the define answer I was looking for, it seems so simple how could I even have missed that? Thanks so much for that!!