Dynamic DNA Explained

Deoxyribonucleic Acid

What is it? 
We're sure you've heard of this term; Deoxyribonucleic Acid. No? How about DNA? Well good news, they are the same! DNA is the shortened way of saying the long molecule's name. DNA is known for its double helix shape.
DNA is made up of chemical bases, four to be precise, A, T, C, and G.
A: Adenine
T: Thymine
G: Guanine
C: Cytosine
These chemical compounds match up to one another; A to T and C to G.  This connection is called a base pair. There is another compound, Uracil, that can attach to Adenine, but this is a result of RNA, not DNA.

Double Helix / A-T and G-C pairing

So what is RNA?
We are glad you asked! RNA (Ribonucleic acid) is similar to DNA. They are both nucleic acids but they do different things. DNA is complex and holds secret messages in its makeup. (It's like a chemical spy holding all the secrets about you!) RNA is the only one who can understand these secrets. RNA, in a sense, translates these messages for proteins and other things; it transcribes the message DNA has.

DNA and RNA are also different in shape. Like we said, DNA has a double helix shape; this shape is like a spiral staircase. RNA however is single stranded. RNA has a a couple different shapes, depending on how its base pairs match up.

Shape of RNA/ C-G and A-U pairing

Where is DNA found?
DNA is found inside the nucleus of the cell. The nucleus is a great place for a nucleic acid! The nucleus is inside the cellular membrane of the cell though. How do we break open the microscopic cell membrane and the nucleus? Dish soap! The dish soap breaks apart the molecules of the cell. Both dish soap and the cell membrane have hydrophobic (scared of water) and hydrophilic (loves water) sides.

Why add contact solution, pineapple juice or meat tenderizer?
DNA is folded and cushioned by protein in the cell. The contact solution is acidic and separates the DNA from the protein.

How come the white stuff is DNA?
The DNA is the white, stringy stuff you see in the top layer of alcohol. Alcohol forms a layer on top of the water because it is less dense. Adding salt to the mixture (at the beginning) helps DNA stick together.  But when in water DNA is dissolved. Adding the alcohol brings the DNA 'out of solution', making it undissolved. This is called precipitation.


Further Information:
http://ghr.nlm.nih.gov/handbook/basics/dna
http://www.usask.ca/education/coursework/mcvittiej/bio30unit1/overheads/1.23.htm