Over the last 40 years, in vitro tissue culture has developed dynamically and has become a popular technique for scientific research in the field of biology. Initially, studies were carried out to develop procedures to obtain callus cultures, cell suspensions, and protoplasts of various plant species. Over time, these cultures have been used to analyze the course of processes and mechanisms that occur at the cellular level, including the course of embryological development, formation of cellular structures, polyploidization, signal transduction, gene expression, and responses to various stress factors. In a minireview, different nutritional, hormonal, atmospheric, and light conditions occurring in in vitro cultures, which are stressful conditions compared to those in ex vitro plant culture, were discussed. In this review, some examples of physiological studies conducted on in vitro culture by Polish scientists are presented, including studies carried out to optimize the composition of media that induce callus and plant regeneration; determine the use of in vitro culture for the preservation of endangered plant species; understand the mechanisms of resistance responses to pathogens, salinity, nutritional stress, and low temperatures; and determine the potential production of plants with different chemical compositions. The potential of sterile plant culture is large and beyond the scope of its current use. Therefore, the number and variety of applications of these cultures will be significantly greater in the future.