Wednesday, April 4, 2012


DNA stands for deoxyribose nucleic acid. DNA is what makes an organism what it is. It is made up of a nucleotides that all bound together by a phosphodiester bond (a bond formed between two phosphate groups). So what is a nucleotide? I'm sure many of you know about the four different bases found in DNA - adenine, guanine, thymine, and cytosine. Those aren't the only components of a nucleotide, though. The other two components needed to make a nucleotide are a sugar (deoxyribose) and a phosphate group.

One of the incredibly fascinating features of DNA is that the bases have extreme selectivity when bonding to one another. Adenine will only form a hydrogen bond with thymine and guanine will only form a hydrogen bond with cytosine, each forming a 1:1 ratio. It is partially because of this (known as Chargaff's rule) that Watson and Crick were able to elucidate the structure of DNA. Although there is much more that can be said on this topic, I won't try to explain anything else. Mainly because I don't fully understand it so there's no way I'm going to be able to explain it to others.

Answers to yesterdays questions: transcription is the processes of copying DNA into single stranded mRNA. Translation is the processing of that mRNA into a polypeptide. A polypeptide is a sequence of amino acids, but a protein is a polypeptide with function.

Do you know what percentage of your genome is different than everyone else's?


Anna Smith said...

Wow this sounds very complicated, I'm gona pretend like I understood what you said!
Is the percentage something really small like 1%?

Universal Gibberish

MOV said...

another great post. I remember being fascinated by all this when I took some of these bio classes in high school and college. Now the fascination has morphed into straight-up confusion. You are making my brain hurt! But in a good, could-use-the-workout, sort of way.

will be back to


Katsidhe said...

Of what I remember of high school, I loved genetics. I still find it fascinating and wonder what it would have been like if I hadn't become sick after graduation on gone on to study it as I'd intended.

nutschell said...

I remember learning about this in my high school biology class for the first time and being really interested. ;)
Great A-Z post!

Jennifer Macfarlan said...

Anna - You are really close!

MOV - Sorry to make your brain hurt, but they say no pain no gain, right? Glad you enjoyed it!

Katsidhe - You should go back to school if you can! It's well worth it in the end.

nutschell - Thanks for stopping by, I'm glad that you enjoyed it!

A Quiet Corner said...

WOW! YOU are a wiz at this! Thanks for teaching us!!...:)JP

Laurie Peel, RP-CRA said...

I love all things science and just over a year ago took an anatomy & physiology course - DNA was covered in exquisite detail. I LOVED it, understood it and even remember it (for a while). Unfortunately, if I don't use it, I lose it, and it's all just a fond memory now... :(

Damyanti said...

I'm becoming wiser every time I visit your blog!!

Look forward to E!

--Damyanti, Co-host A to Z Challenge April 2012

Twitter: @AprilA2Z

Lily Tequila said...

I would guess a very small percentage- or cheat by Googling! DNA is so beautiful to look at, if baffling to fully understand :-)