## 3 Discussion
Conversely, the pupae did not show any significant alterations in all examined parameters. Clarifying this concept is challenging. In contrast to our findings, studies suggest that the early stages, including pupae and larvae, display a greater susceptibility to stressors such as metals, temperature, and UV radiation [40; 41; 42]. A large body of animal studies supports the notion that stressful situations reliably produce hyperglycemia via the metabolic effects of increased corticosterone secretion [43; 44]. Also, exposure to EMF can lead to changes in sugar levels [11; 45]; however, our findings revealed no significant alterations in total hemolymph sugar levels. This lack of an effect might be attributed to the dominant influence of severe food deprivation induced stress, which could have overshadowed the impact of EMF exposure. This is also the likely cause for the absence of notable changes in the metamorphosis rate, though many insect studies indicate that an extremely low-frequency EMF (below 100 Hz, 0.5-7 mT) is able to affect longevity and developmental dynamics by shortened developmental time, reduce number of enclosed insects, survivability, as well as weakened oviposition in subsequent generations [46; 47; 48; 49]. During the experiments, anomalies were observed in adults that had emerged as a result of the prolonged exposure of larvae and pupae to a 7 mT EMF. Other studies also demonstrate that an extremely low-frequency EMF (<100 Hz) can cause cellular harm and irregularities in the development, e.g., internal gut damage in the adult and larval stage or fluctuations in asymmetry and an increased frequency of abnormal phenotypic traits [46; 50; 51]. Elevated stress levels initially serve an adaptive purpose, as seen in responses like the flight-or-fight reaction. However, these elevated stress levels can transition into a pathological state if they persist for prolonged periods [52]. Continuous activation of the stress response over an extended duration (as was the case with the entire developmental cycle exposure to EMF, from the larval stage) triggers physiological transformations leading to the depletion of energetic and molecular reserves, the accumulation of toxic compounds and disruptions in regulatory pathways that may be reflected in the disturbance of transformations and success of metamorphosis [53]. It is known that exposure to EMFs can induce morphological and physiological changes in stress-related systems [11; 54]. The current knowledge shows that biogenic amines (BA), such as dopamine (DA), octopamine (OA), serotonin (5-HT), and tyramine (TA), act as neurotransmitters, neuromodulators, or neurohormones and are involved in the non-specific stress response and their levels change in various insect species under unfavorable conditions. They modulate behaviors and peripheral and sensory organs, enabling the insect to respond correctly to external stimuli [36; 54; 55; 56; 57]. DA and 5-HT are involved in regulating locomotion and play a role in modulating arousal, feeding behavior, aggression, and learning processes. OA is the most frequent insect amine and, along with its precursor, TA, serves as the invertebrate equivalent to the vertebrate adrenergic neurotransmitters [58; 59; 60]. As a \"stress hormone\", OA has a role in controlling various behaviors, such as flight and aggression, and is responsible for the mobilization of energy that prepares insects for higher metabolic activity related to the stress response and is useful during the recovery period. In the periphery, OA increases heart rate and may modulate ventilation and stimulate mobilization from muscles [58; 61; 62; 63; 64]. The activation of energy through the influence of BA occurs due to the triggering of glycogen conversion into trehalose and glucose and the oxidation of trehalose, along with the release of lipids from the fat body [65; 66].