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Biology-Related Homework Help Genetics and Developmental Biology Topic started by: EvaRL on Jan 6, 2015



Title: why are nitrogen bases called bases?
Post by: EvaRL on Jan 6, 2015
Why are nitrogen bases called bases if they're acids, because they're part of nucleic acid?


Title: Re: why are nitrogen bases called bases?
Post by: bio_man on Jan 6, 2015
This is a clever question, something I have never thought about. I did some research for you and found a resource that explains it in detail:
Ammonia as a weak base

Quote
All of the compounds we are concerned with are derived from ammonia and so we'll start by looking at the reason for its basic properties.

For the purposes of this topic, we are going to take the definition of a base as "a substance which combines with hydrogen ions (protons)". We are going to get a measure of this by looking at how easily the bases take hydrogen ions from water molecules when they are in solution in water.

I have included the source below.


Title: Re: why are nitrogen bases called bases?
Post by: EvaRL on Jan 6, 2015
Thanks. I tried to read the page but it was way too much chemistry for me. Would it be correct to say that in the case of nitrogen bases, "base" is not being used in its usual chemical sense?


Title: Re: why are nitrogen bases called bases?
Post by: ortho2122 on Jan 6, 2015
I'm not sure why you are in such a hurry to disavow the acid-base chemistry of the nitrogenous bases of nucleic acids. They act as bases: they are proton acceptors which makes them Bronsted-Lowry bases by definition. They are not important bases when it comes to biological buffering systems, and we tend to think of them more for their information content via complementary base-pairing, but they are nevertheless "bases." Why is that a problem?


Title: Re: why are nitrogen bases called bases?
Post by: bio_man on Jan 6, 2015
They act as bases: they are proton acceptors which makes them Bronsted-Lowry bases by definition.

Precisely!