MFM Molecular Test 3 Practice

Biochemical cues from the extracellular matrix provide signaling that guides how tissues form, how cells decide what to become, and how they maintain their organization over time. Cells sense the ECM through receptors like integrins; when these receptors bind matrix proteins such as collagen, laminin, or fibronectin, they trigger intracellular signaling pathways (for example MAPK, PI3K/Akt, and Rho-family signaling). These pathways influence gene expression, cytoskeletal arrangement, and cell behavior, directing tissue morphogenesis and differentiation. The ECM also stores and presents growth factors and creates mechanical cues (stiffness and composition) that shape cell fate decisions, contributing to tissue homeostasis through ongoing remodeling and signaling balance.

Protein synthesis, while essential, is governed mainly by intracellular gene expression and ribosomal activity rather than direct ECM cues. Muscle contraction relies on excitation-contraction coupling and sarcomeric machinery, with ECM providing structural context but not serving as the primary source of biochemical signals for contraction. Digestive enzyme secretion is predominantly controlled by neural and hormonal signals.