Miguel de la Torre, Aina Duch, Ferran Cuevas and Andra Dumitru

    IES Matilde Salvador, Castelló de la Plana, Spain


    Miguel de la Torre, Aina Duch, Ferran Cuevas and Andra Dumitru, authors of this work, have showed us that the DNA (deoxyribonucleic acid) is present in all the living beings. This is formed by long chains of amino acids and proteins, that are responsible of the transmission. The main function of the DNA molecule is to storage on a long-term basis. The segments of DNA that bring genetic information are called genes, but the other sequences of DNA have structural purposes.


    The main aim of study of the genetics are the genes, for segments of DNA and RNA. The appearance of a person (height, colour of the hairs, of skin and of the eyes) is determinated for the genes. Also they treat the following subjects:


    The genetic revolution, the human genome, the clonation, assisted reproduction, the stem cells and bioethics.


    To the practical part they have realised an experiment, with a banana, to show us that everything living being has DNA. Therefore, any species of fruit has been able to suffer alterations or mutations along the history until finishing being the banana that nowadays we know, because of the natural selection of the Darwin's evolution theory.


    In this experiment, they triturated the banana in the beater with some salt and water at maximum speed during 15 seconds. Adding the salt neutralises the negative load of the substances of the DNA. Later, they filtered it, and obtained a reasonable quantity, added it detergent (the organelles that contain the DNA are surrounded by a membrane formed by lipids and with the detergent this membrane breaks), and stired up softly without doing foam and leaved to rest 10 minutes. Next they added it a few quantity of pineapple juice (the pineapple juice degrades all the proteins that there are in the cell, this does that only remains the DNA in the mix). They poured alcohol, that is a polar substance less dense that will do the DNA remain above. Finally, with a toothpick, they extracted the DNA.


    The genetic conditions us, contributes us some unic qualities for each human. For this reason this work has been very interesting for them since we don’t know a lot about this subject that actually is very important.


    Almera Queipo, Jesús; Bellés Moliner, Jordi; Camacho Pérez, Javier; Climent Rull, Marina