Gradually, the number of staff was rising as well as the number of lectured subjects along with the scope of the research programme. This brought up the search for an optimal model for the structure of biological departments. At the beginning, there were four independent departments, from 1972 reduced to only two: Department of General Biology headed by Prof. Milan Praslička and Department of Special Biology headed by Prof. Robert Hončariv. Biological research gradually branched into several directions. In addition to radiobiological issues, the field of Space Biology started to be developed in the framework of the international co-operation programme “Interkozmos”. The research was oriented towards the influence of micro-gravitation and other factors of space flight on metabolism of lipids and nucleic acids of organisms in different stages of ontogeny. Later the chronophysiological study of biological rhythms of selected metabolic parameters and hormones of rats was developed. In the field of population genetics the research of anthropologic markers of the Romany ethnic group in the area of Eastern Slovakia was established. Zoological research was focused predominantly on the species diversity of amphibian and molluscan fauna. The researchers in botanic fields continued in the study of cytogenetic changes of plants induced by chronic gamma radiation, later the research on medicinal plants and natural compounds was rapidly developed and focused predominantly on bioactive substances and breeding of new varieties of medicinal plants. In the 1980s a new direction in plant biotechnology was going ahead. Since 1985, the Department of General Biology was headed by Prof. Eva Mišúrová. With the gradual rise in the number of subjects lectured and research duties conducted, the predispositions were formed for further re-structuring of the biological departments. This resulted in the creation of four biological departments in 1990: Department of Anthropology and Zoology, Department of Cell and Molecular Biology, Department of Animal Physiology and Department of Experimental Botany and Genetics. In 1999 the Department of Anthropology and Zoology was transformed into the Department of Zoology and Ecology.

In nineties the traditional radiobiological orientation of research was gradually leaving. The majority of research projects were devoted to the study of natural medicinal sources with anti-viral and anti-cancer activity, research of the mutagen and carcinogenic effects of environmental factors, and to the study of carcinogenesis and experimental prevention and treatment of tumours. Zoological research was aimed at the study of soil and water environments in relation to abiotic factors.

In 2002 the need for better coordination of scientific research and higher efficiency of the educational process led to the new organisation structure of the faculty. The Institute of Biology and Ecology putting together the former four departments was established and the departments were transformed into the academic workplaces of the Institute.