This article examines the structural foundations underlying the processes of adaptation and integration in the small intestine. Particular attention is paid to the morphological and histological features of the intestinal wall that ensure functional adaptability to varying physiological conditions. The study analyzes the role of epithelial cells, villi, crypts, vascular and nervous components in maintaining integrative interactions between digestion, absorption, immune defense, and neurohumoral regulation. The adaptive capacity of the small intestine is considered in the context of structural plasticity, cellular renewal, and regulatory mechanisms that support homeostasis. The findings contribute to a deeper understanding of the structural–functional relationships essential for the integrative activity of the small intestine.

Small intestine, structural adaptation, integration

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