The authors discuss the results of updating SRSTI subject classes 34 Biology and 76 Medicine and Healthcare. Within these classes, the subject headings to a great extent appear to be associated. Within the SRSTI master version, the mentioned classes are well structured. However, when preparing 2025 SRSTI master version, the analysis of their subject and structural organization evidences on t he n eed t o m ake t he s et o f c hanges a nd a mendments to the Rubricator due to the rapid development of fundamental and applied disciplines within the earth sciences. To update class 34 Biology, 52 changes had to be made to its structural organization; with new subject headings making 67.3% of changes and 32.7% updates of subject headings naming. Significant changes are made to the areas of developmental biology, cell biology, plant physiology, microbiology, virology and anthropology. Thus, SRSTI master version class 34 Biology is to comprise 25 subclasses systematized with 306 subject headings on the 3-rd hierarchical level. To develop class 76 Medicine and Healthcare, 51 changes are to be implemented into the structural organization, with new subject headings making 70.6%, 25.5% updates to the headings naming, with 3.9% headings excluded. To the utmost, the changes are made to the subject areas of medical cybernetics and informatics, clinical medicine, clinical pharmacology, hygiene and epidemiology as well as healthcare organization and administration. Finally, class 76 Medicine is to comprise 10 subclasses, represented by 189 subject headings on the 3-rd hierarchical level. 182 new polyhierarchical links between the subject headings have to be introduced to the SRSTI reference aids upon the updates to class 34 Biology and 76 Medicine and Healthcare; with the most frequent link “see also” which evidences on the serious intensification of interdisciplinary component within the structure of SRSTI 2025 master version.