DNA is short for deoxyribonucleic acid. DNA is very special as it is holding the genetic code for all cells in our bodies.
That’s correct. All cells in our bodies use DNA as a sort of instruction manual.
Now, in case you would wish to take away that statement’s importance, you may say that DNA is a long nucleotides spiral chain. Sure, but it is so much more.
So, we have all of these nucleotides in these two long chains that are twisting around each other. This twisting shape is what we call a double helix.
That spiral ladder comes with the capacity of winding and unwinding so that the chain of the nucleic acid can duplicate itself. The process of duplication is called replication, and it happens all the time when a cell divides.
DNA’s Down Time
When cells are in their normal states, DNA will not duplicate, and it merely is looking like white strands. In the world of Science, the word chromatin is used for describing that DNA.
Chromatin is found in numerous organization levels. It will change the organization’s overall structure (not chemically, just physically) at different stages of a cell’s life. Usually, the nucleic acid chains are sitting around uncoiled as just loose strands.
When cells start to reproduce, they will condense to wrap up tightly. This tightly wound DNA is what we call a chromosome. A chromosome looks like a long, limp hot dog. You can also find these chromosomes in pairs. In practically all organisms, you can find the DNA in the organism’s nucleus.
Chromosomes are working in the cell together with other nucleic acids for building proteins and helping in the process of cell replication. Most likely, you will find messenger ribonucleic acid (mRNA) with the DNA in the cell’s nucleus while you will find transfer ribonucleic acid (tRNA) outside of the cell’s nucleus, floating around in the cell.
The DNA Instruction Manual
Just keep in mind that DNA is actually the instruction manual for organisms and even though all of our organisms are using the same 5 nucleic acids for building and replicating DNA, it actually is the order that is making us the ones we are. We’ve got the 3 pyrimidine bases (thymine, cytosine, and uracil) and the 2 purine bases (guanine and adenine).
All organisms on Earth have a different order and number of base pairs. Orders of base pairs determine our physiology. If we have a group of 3 DNA base pairs, they may code for 1 amino acid.
And at the time these strings of mRNA leave the cell’s nucleus with that information, the construction of long chains of amino acids may occur. At that time, we have produced proteins that are capable of doing work for our cells. Everything is going back to the order and number of base pairs within the original strand of DNA.
Next lesson: Evolution
Last Updated on November 24, 2020.