A Ride into the World of Genetics!

It was a bright and lovely evening, the sun slowly disappearing behind the white fluffy clouds, so as to say goodbye for the day. The tall coconut trees stood upright, not swaying to the force of wind. The birds returned to their homes after a long day. As I stood in the midst of the huge wheat field, observing the mother sparrow feeding its young ones, I heard someone shouting out my name. I turned to see my dearest friend and fellow science enthusiast, Krithika.

Me : Hey, Krithika! Good to see you!

Krithika : Hey, Appu! Good to see you too! Did they arrive here yet?

Me : No! I have been waiting for a long time. I guess Boomika must be busy editing her novel. And, Kicha should be in Nehru mama’s sweet shop. No wonder he visits the shop everyday. Who can resist Nehru mama’s homemade sweets !!

Krithika : So when are we doing our next experiment ? It’s been days since we did one.

Me : Come to my house tomorrow. Let’s do the static electricity experiment with balloons Krithika : I am already so excited!

I saw Kicha running towards me. He finally stopped, gasping for breath.

Me : Kicha, why are you so late? Catching his breath slowly, Kicha started explaining.

Kicha : Sorry Appu. I was doing exercises with my father. That’s why I came late. Acchan promised me to buy my favorite helicopter if I do as he says. So, I can't refuse this golden offer.

I saw Boomika casually walking towards us. Her hair was unusually loose. Her twinkling eyes reminded me of my mother.

Boomika : Hello friends!

Me : Hello Miss writer! Have you finished exploring your imaginary world?

Boomika : Yes Appu!

We decided to play a game of hide and seek while we waited for Boomika’s father to arrive. He had promised to take us to my father’s science lab. I heard the sound of a vehicle somewhere far away from us. I peeked out and looked at the roads, it was Boomika’s father!

Me : Hey Boomika, your father is here. Her exuberant face turned pale and fearful.

Boomika: Oh god! I am in trouble. If he sees me with loose hair, he will be furious. She immediately started braiding her hair.

Me : Your braid reminds me of something.

Boomika :What is it?

Me: Do you know what DNA is?

Boomika : What is that Appu?

Me : Let me explain to you clearly.

DNA is the repository of genetic information in our body. DNA is deoxyribonucleic acid. Nucleotides are the building blocks of DNA. They are composed of nitrogenous base, deoxyribose sugar and phosphate group. DNA is double stranded, helical structure. The strands are complementary and are linked by hydrogen bonds between the nitrogenous bases.

Boomika : Now, I understand why you connected my braid with DNA!

Krithika : In fact, each and every cell in our body has DNA. It carries genetic information in our body. DNA has genes, which code for proteins. Genotype is an individual’s collection of genes. When genes are expressed in our body, proteins are formed. The expression of genotype influences the observable characteristic traits in our body, known as phenotype.

Krithika : Hey Appu! Your father is a biologist right? Why don’t we ask him about DNA? I am sure that he has some cool facts to share.

Me : Nice idea Krithika. Let’s go!

We set out to my father’s lab in Boomika’s car, along with her father. We reached our destination. The little building looked polished and neat. The marble floors reflected the bright lights in the room. Scientific equipment such as compound microscope, beakers, flasks, bunsen burner were neatly arranged on the work table. My father, popularly known as the science geek, was keen on dissecting the butterfly, which was lying dead with its wings cut.

Scientist : Hello children! What a pleasant surprise!

Boomika : Hello, uncle! It’s good to see you.

Me : Acchan, can you tell us about how DNA was discovered?

Scientist : It’s glad to see that young kids are interested in science. Let me explain to you how DNA was first discovered.

In the 1860s, Swiss chemist Friedrich Miescher conducted experiments on extracting protein components from white blood cells. He found a mysterious substance extracted from the nucleus of the cell with non-protein properties and high phosphorus content. He called this mysterious substance “nuclein”. In 1951, Franklin and Wilkins obtained images of DNA from an experimental technique. Finally, In 1953, two scientists Watson and Crick proposed the double helical structure of DNA based on the findings of Franklin and Wilkins. This is how we discovered DNA and the structure of DNA!

Krithika : Wow uncle! It’s mind blowing how they discovered the structure of DNA.

Scientist : Let me show you kids a method to extract this DNA. Are you ready for a small science experiment?

Krithika : I am all ready!

Scientist : We are going to extract DNA from strawberries. So, first we have to place one strawberry inside the zip lock cover and smash it! Who is the strongest among you? Everyone pointed towards Kicha.

Kicha : It’s me, uncle! Kicha smashed the strawberry into pieces.

Scientist : Well done Kicha! Now let’s add extraction buffer solution to the smashed strawberry. This will extract DNA from the cells.

Boomika : Wow! I feel so tempted to drink the juice! It looks yummy!

Scientist : Now, let’s create the DNA extraction liquid in the plastic cup. This preparation plays a role in dissolving DNA in the solution. To prepare the extraction liquid, add 2 teaspoons of detergent, 1 teaspoon of salt and half cup of water.

Kicha : This is such an interesting experiment uncle!

Scientist : Yes it is, Kicha. Now, let’s stir this mixture and again replace it inside the zip lock cover. Now, use your strength and smash this again. Kicha smashed the mixture inside the zip lock cover.

Scientist : Okay, now let's extract the liquid from this thick mixture. We will need a coffee filter and a paper cup. First, we have to pour the contents onto the coffee filter. And then, squeeze it to extract the fresh liquid. Who is going to squeeze the contents?

Krithika : I will do it uncle! Krithika squeezed the filter paper. The fine extract settled at the bottom of the paper cup.

Scientist : Good job Krithika! Let's put these contents back into the plastic cup and add cold rubbing alcohol. Alcohol isolates DNA from the extract. Now, all we have to do is wait for a few minutes and you can observe the extracted DNA as a white cloudy substance.

A few minutes later,

Boomika : Look at the solution everyone. I can see a white object resembling a thread floating above in the solution.

Scientist : Good observation Boomika! That’s our DNA! Let’s take a wooden stick and pick the DNA from the solution.

Krithika : Wow! This is awesome.

Me : I feel we should do experiments like these often.

Kicha : Yes Appu! Thanks uncle for explaining to us about DNA.

Scientist : You are most welcome kids!