Have you ever thought about what thing makes you be what you're? That thing that makes you different from everyone else? Where are you, as an elemental being? Where are all those information which told your body to be just like it is? Well, I just had a biology class with a nerdy-vegan-lesbian-feminist looking woman (no offence) with a doctorate in biochemistry who remembered me how stupid I'm so when I got home I started to study a little deeper from what I knew and I'm gonna tell you about what I learned yesterday.
The amazing DNA. A polymer about thousands of nucleic acids placed one beside another forming a thread which links to another thread of nucleic acids. The difference between the four nucleic acids that compose the DNA lies on their nitrogenous base. That base could be Adenine, Guanine, Thymine and cytosine. It's just some carbon, hydrogen, oxygen, nitrogen and phosphorus in the right place. Four elements that contains all the information about your body. Those nucleic acids are the elemental you and that's because the DNA is the base for transcription and translation, which is the essential process that does your cells to build proteins since the beginning of being you. And those proteins interact with the rest of your cell's molecules, forming an important part of the majority of all the chemical reactions inside your cells working as enzymes. In conclusion, depending of the order of the nitrogenous bases that conforms your DNA, your cells will produce certain proteins which will interact into some chemical reactions inside you. That makes you be what you're. All living things are just a high level pattern of chemical reactions inside a vesicle composed of phospholipids which can react with external agents.
But hey, how does the DNA tell your cells about what proteins do it have to do? Well, the answer is simple and also it's complex. The simple thing is that a protein is just a chain of different amino acids (polypeptide) placed in a certain order. The amino acids are linked among themselves inside the ribosome. It has two concavities; in one of them is the incoming messenger RNA and in the other one is the in-process polypeptide. Each amino acid has specific anticodons (which is an unit made of three nucleotides) which reaction with an unique triplet of nucleotide inside the messenger RNA with the help of the Aminoacyl tRNA Synthetases. So, depending of the order of the nucleotides inside the mRNA, your cells will make a certain protein. But what's mRNA? It's a sequence of nucleic acids but with a different carbohidrated bases (with an hydroxide in the carbon number two) which's produced from the DNA (without that hydroxide in the carbon number two) using some enzymes. The way those enzymes do this work is by using the fact that some nitrogenous bases attract themselves (adenine with thymine or uracil (this one is for the RNA) and guanine with cytosine) so you can copy a DNA chain with it's contrary nitrogenous base in the RNA. The anticodons of the amino acids works in the same way, so they will be attracted by the contrary of the nitrogenous bases of the RNA, being themselves identical with the DNA. That's why the DNA is where all of your information is locked-up.
DNA's size is about 20 Å in diameter and 34 Å in length. It's located inside the cell nucleus. There're some grievous illnesses with a bad self-replication of the DNA like cancer, where some nucleotides are poorly replicated so it's mRNA makes ribosomes build other proteins that you don't need and sometimes they could be harmful to your body. There're a lot of things that can produce cancer so I recommend not to worry about it and live your life. Smoke, eat some transgenic fruits and jump inside an x-rays room, what does it matter? You and me, we both're gonna die someday. Try to do something interesting with your life, make it worth. Otherwise you can listen to this wise advice from Morty: "Nobody exists on purpose, nobody belongs anywhere, everybody's gonna die. Come watch TV."
Live long and prosper.