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Metali su prirodna sastavnica Zemljine kore, ali njihova koncentracija u okolišu se neprestano povećava uslijed antropogenih utjecaja. Teški metali mogu uzrokovati direktna i indirektna oštećenja važnih bioloških molekula, a njihova akumulacija u hranidbenom lancu predstavlja opasnost za sve organizme u okolišu. Cilj istraživanja bio je utvrditi učinak teških metala, kadmija i cinka te njihovih smjesa na stabilnost genoma klijanaca duhana Nicotiana tabacum L.. Cink i kadmij su kemijski vrlo slični teški metali pa kadmij može ometati vitalne, biološke reakcije u biljkama, zamjenjujući cink. Iako je pojedinačni utjecaj tih metala u biljnim organizmima detaljno istražen, njihovo međudjelovanje nije dovoljno poznato. U tu svrhu klijanci duhana su rasli mjesec dana na hranjivim podlogama uz dodatke različitih koncentracija metala i njihovih kombinacija. Razina oštećenja i promjene u molekuli DNA duhana nakon tretmana su procijenjeni metodom komet-testa i metodom nasumično umnožene polimorfne DNA (RAPD, engl. Random Amplified Polymorphic DNA). Iako su rezultati komet-testa pokazali oštećenje DNA djelovanjem teških metala kadmija i cinka na klijancima duhana, svakog zasebno i u kombinaciji, rezultati metode RAPD nisu pokazali promjenu u polimorfizmu DNA u niti jednom od tretmana. Komet-test se pokazao kao osjetljivija metoda pri detekciji oštećenja DNA nastalih teškim metalima za razliku od metode RAPD. Metals are natural components of the Earth’s crust but their concentration is constantly increasing due to anthropologic influences. Heavy metals can cause direct and indirect damages of vital biological molecules and their accumulation in the food chain is an immediate menace for all organisms in the environment. The objective of this research was to determine the effect of heavy metals, cadmium and zinc and their mixtures on the genome stability of tobacco seedlings. Even though the influences of these metals alone in plant organisms are researched in great detail, their interaction is not well known. Since zinc and cadmium are chemically very similar heavy metals, cadmium can interfere in vital, biological reactions inside the plants by replacing zinc. Seedlings were grown for 30 days on nutrient medium with addition of different metal concentrations and their mixtures. The extent of DNA damage and DNA alterations after the treatment were evaluated using the Comet assay and RAPD (Random Amplified Polymorphic DNA) method. Even though the results of Comet assay showed statistically significant DNA damage caused by heavy metals, individually and in mixtures, the results of RAPD analysis did not show any change in DNA polymorphism in all of the treatments. Comet assay proved to be a more sensitive method in detection of DNA damages caused by heavy metals in comparison to RAPD analysis.

Neandertalci su hominidi koji su naseljavali Zemlju u periodu od 400,000 godina. Pretežno su obitavali na prostorima Europe te Zapadne Azije. Prije 27,000 godina, gubi im se trag te se danas smatraju izumrlima. Njihov način života te građa su bili oblikovani surovom klimom te okolišem koji je bio uobičajen u pleistocensko vrijeme na Zemlji. Bili su veoma snažni i imali veliku mišićnu masu. Zbog tog razloga su trebali i veliki unos kalorija, velike lovine. Imali su oruđe i oružje te su proglašeni karnivorima, odnosno mesožderima. Prije 40,000 godina, na prostore Europe stiže Homo sapiens te kroz neko vrijeme stiže i do teritorija neandertalaca. Postoje samo nagađanja o njihovom susretu te životu nakon susreta. Nedavna istraživanja genoma neandertalaca sugeriraju veliku bliskost našem genomu te čak mogućnost interbreedinga. Teorije koje se predlažu oko nestanka neandertalaca uključuju; promjene u okolišu, kompeticiju sa suvremenim ljudima te genocid. Znanstveni svijet se nije izjasnio u potpunosti po pitanju navedenih teorija, no pretežito naginje teoriji krvave kompeticije sa suvremenim čovjekom. The Neanderthals were hominids that habituated Earth in period of 400,000 years. They preferably maintained parts of Europe and West Asia. Since 27,000 years ago they are nowhere to be found and nowadays are considered extinct. Their way of life and the way they were physically built were shaped by harsh environmental and climate changes. They were very strong with great muscle mass. That was the main reason they needed large amounts of calories, large prey. They were well equipped with weapons and tools, and are considered to be carnivores. Homo sapiens arrived 40,000 years ago, on the plains and hills of Europe and in some time made it all the way to the Neanderthal’s territory. There are guessing about the way they’ve met and their lives after the meeting. Recent Neanderthal genome researches suggest that they were genetically very close to us and that there are possibilities of interbreeding. Neanderthal extinction theories that are suggested are; harsh environmental conditions, competition with modern people, and genocide. Science world has not been concrete about those theories but they are leaning towards theory about bloody competition with modern man.