Skip to main content

The Natural Polymer That Controls Life - DNA!

Some life-forms on earth. PC: Micro
[5 min read]

In today's post on MATESA TODAY, we want to learn about a natural polymer (giant molecule) that controls all life-forms on Earth - in plants, animals, micro-organisms, etc. This wonderful material carries the instructions that are associated with the transmission of genetic information: the shape of your nose, the colour of your eye, people's height, their skin colour, etc. 

This publication gives us some basic insight into DNA. Sounds quite biochemical, but it has got the Materials Science aspect too - Polymers; though materials scientists primarily deal with synthetic polymers. But we usually take inspiration from nature to do new stuff, more technically, develop novel products. After all, we call it genetic material!

BASIC TERMS DEFINED
Polymer means "many parts" and designates a large molecule made up of smaller
repeating units.
Monomer is a molecule that combines with other molecules of the same or
different type to form a polymer.

WHERE IS IT FOUND?
DNA is found in the nucleus of the cell. The nucleus is the control center, or the brain of the cell, so it would make sense that DNA is found there. Nevertheless, some amounts of DNA can be found in the mitochondrion or chloroplast. DNA is a nucleic acid and it contains the genetic instructions for the function and development of living things. The role of DNA is to store genetic information.

NOW TO THE CHEMISTRY
WHAT IS DNA MADE OF?
DNA biopolymer
The DNA macromolecule is a natural polymer (biopolymer)  and it stands for deoxyribonucleic acid. The monomer units of DNA are nucleotides, and the polymer is known as a polynucleotide or nucleic acid. It has been popularly tagged as the ''king of molecules''. Can you tell why? Save it for the comments.

Each nucleotide consists of a 5-carbon sugar (pentose deoxyribose), a nitrogen-containing base attached to the sugar, and a phosphate group. There are four different types of nucleotides found in DNA, differing only in the nitrogenous base. The four nucleotides are given one letter abbreviations as shorthand for the four bases.
- A is for Adenine (C10H12O5N5P)
- C is for Cytosine (C9H12O6N3P)
- G is for Guanine (C10H12O6N5P)
- T is for Thymine (C10H12O5N5P)

Two DNA strands form a helical spiral, winding around a helix axis in a right-handed spiral. The two polynucleotide chains run in opposite directions. The sugar-phosphate backbones of the two DNA strands wind around the helix axis like the railing of a spiral staircase.The bases of the individual nucleotides are on the inside of the helix, stacked on top of each other like the steps of a spiral staircase.  The other groups of biopolymers are polypeptides (proteins) and polysaccharides (sugars). The closest relative of DNA is RNA (ribonucleic acid), which is a single strand.

HOW DOES DNA WORK?
Comparing DNA and 'sister' RNA

Our cells read the genetic code three bases at a time in order to generate proteins (also biopolymers) that are essential for growth and survival. The DNA sequence that houses the information to make a protein is called a gene. Each group of three bases corresponds to specific amino acids, which are the building blocks of proteins.

For example, the base pairs T-G-G specify the amino acid tryptophan while the base pairs G-G-C specify the amino acid glycine. Some combinations, like T-A-A, T-A-G, and T-G-A, also indicate the end of a protein sequence. This tells the cell not to add any more amino acids to the protein.

Proteins are made up of different combinations of amino acids. When placed together in the correct order, each protein has a unique structure and function within your body.

HOW DOES DNA CODE A PROTEIN?
DNA coding of Protein. PC: ResarchGate

So far, we’ve learned that DNA contains a code that gives the cell information on how to make proteins. But what happens in between? Simply put, this occurs via a two-step process:

First, the two DNA strands split apart. Then, special proteins within the nucleus read the base pairs on a DNA strand to create an intermediate messenger molecule.

This process is called transcription and the molecule created is called messenger RNA (mRNA). mRNA is another type of nucleic acid and it does exactly what its name implies. It travels outside of the nucleus, serving as a message to the cellular machinery that builds proteins (ribosome).

In the second step, specialized components of the cell read the mRNA’s message three base pairs at a time and work to assemble a protein, amino acid by amino acid. This process is called translation.

FUN FACT
PC: Quartz

One gram of DNA can potentially hold up to 455 exabytes of data, according to the New Scientist. For reference: There are one billion gigabytes in an exabyte, and 1,000 exabytes in a zettabyte. The cloud computing company EMC estimated that there were 1.8 zettabytes of data in the world in 2011, which means we would need only about 4 grams (about a teaspoon) of DNA to hold everything from Plato's writings through the complete works of Shakespeare to Beyonce’s latest album (not to mention every photo ever posted on Social Media).

Encoding digital information (in 0's and 1's) on DNA is not a big deal. The herculean task is the difficulty in retrieving the information stored on DNA. Maybe with the spate of advances in technology and research, it can be possible. Want to take up the challenge?

THE BIG QUESTION???
PC: sciencemag

Given the marvellous and magnificent makeup and mechanism of DNA, do you think it came about by chance, as in the Theory of Evolution, or it was specially and deliberately designed by the Creator? Let us know your thoughts in the comment section below. You can also share your thought on our various social media platforms.

Credits: Quartz, atdbio, healthline, The Elements of Polymer Science and Engineering (2nd Edition)

In a later article, we might look at the DNA much into detail in an even greater Materials Science perspective. Stay tuned for some delightful polymer science chemistry.

Read Also: Be A Survivor!

Send us message on WhatsApp. Visit our Homepage for more interesting material!

https://bit.ly/2VfJWwz

Comments

See Also

MATESA SPORTS SEAT - Exclusive Interview

Mr Kwame Attakora-Seater of The Week This is the maiden edition of Sports Seat. It is an exclusive interview with the Sportsmen of MATESA - published weekly. The first interviwee to sit on Sports Seat is Mr Kwame Boakye Attakora. He tells about himself, MATESA and also sports (football). Who is Mr Kwame Boakye Attakora? I have always found this question very complex to answer mainly because as a person I am constantly evolving as a result of my experiences but I guess basically i am a Fante-Ashanti boy working towards making my hopes and dreams a reality. What was your experience like in secondary school? Secondary School was fun, like all my experiences. I was in Achimota School between 2010 and 2013. Funny thing is I didn’t actually plan on going there. Growing up my dream secondary school was PRESEC, Legon but I ended up at Achimota due to an error on my part when I was selecting secondary schools to attend. I chose PRESEC, Legon but mistakenly wrote down the Ac...

The Quality of Locally-manufactured Cornmill Grinding Plates

Corn mill A KNUST research has revealed people who consume corn-related foods risk contracting all kinds of cancers According to the research, the locally manufactured machine used to grind the corn into dough food wears off faster into the dry maize, thus contaminating it. A study by two lead researchers at the Kwame Nkrumah University of Science and Technology (KNUST) has revealed that consumers of corn-related foods risk contracting all kinds of cancers. The research was undertaken by Prof. Kwofie, who is the Dean of the Faculty of Mechanical and Chemical Engineering (former) of the College of Engineering, and Dr. Anthony Andrews (now Professor) , the Head of Department (former)  for Materials Engineering . The study found that the metals used for the milling plates usually wear off when the food products are being grinded. This, the study said, opens consumers to the risk of contracting cancer, since the metals contain 'iron overloads' which are poisonous. ...

Introduction to Glass Science and Technology

Technological History The presence of glasses in our everyday environment is so common that  we rarely notice their existence. Our current casual attitude toward the family of materials known as glasses has not always existed. Early Egyptians considered glasses as precious materials, as evidenced by the glass beads found in the tombs and golden death masks of ancient Pharaohs. The cave-dwellers of even earlier times relied on chipped pieces of obsidian , a natural volcanic glass, for tools and weapons, i. e., scrapers, knives, axes, and heads for spears and arrows. Humans have been producing glasses by melting of raw materials for thousands of years. Egyptian glasses date from at least 7000 B.C. Ancient Egyptian glass beads. PC: Science News How did the first production of artificial glasses occur? One scenario suggests the combination of sea salt (NaCl) and perhaps bones (CaO) present in the embers of a fire built on the sands (SiO 2 ) at the edge of a saltwat...

Personality of The Week: Prof. Samuel Kwofie

Prof. Samuel Kwofie To end this month's Personality Dialogue is the first Professor of Materials Science and Engineering in Ghana, Prof. Samuel Kwofie. He shares with us his rich knowledge and experience. Enjoy the read as you learn along. PROFILE Prof. Samuel Kwofie is the first professor of Materials Science and Engineering in the country. He lectures at the Department of Materials Engineering at the Kwame Nkrumah University of Science and Technology. He is the immediate past Dean of the Faculty of Mechanical and Chemical Engineering, formerly the Faculty of Chemical and Materials Engineering. He is an alumnus of Independence Hall in KNUST and Ghana Senior High Technical School (GSTS-Takoradi). He hails from Elmina in the Central Region. His skills and expertise include Powder Metallurgy, X-ray Diffraction, Mechanical Testing, Scanning Electron Microscopy, Failure Analysis, Mathematical Modeling, Experimentation, Characterization, Electron Microscopy, among others. ...

Be A Survivor -- A Poem By F. Agyemang

Many across the globe are bearing the brunt of Covid19. Some who haven't experienced it can't really imagine its consequences on people and economies. Let us thus relieve ourselves of the stress with this exhilarating poetic piece by @cocajuana_pens You can call me Covid I'm more dangerous than conflict I have no limit And I kill without mercy Cos I have no vaccine Just don't dare me I might end your destiny I'm so wicked! But you can avoid me Stay at home Give a distance And do no hommies For instance If you have to sneeze or cough Just cover it off Don't do it raw Else it'll be an issue So kindly use a tissue Hand washing should be regular That's the normal routine Do it with soap under running water Even if you haven't eaten Wondering how to keep clean? Use a hand sanitizer Just like many diseases I know I won't last forever A vaccine will be made And I will be slayed Until then, you have to be a survivor ...