The study investigates the structural organization and dynamics of biomolecular condensates, specifically focusing on the interactions between nucleolar granular components (GCs) and the proteins that form them. Using a combination of small-angle neutron scattering (SANS), fluorescence recovery after photobleaching (FRAP), and coarse-grained molecular dynamics simulations, the researchers provide insights into the spatial inhomogeneities and network-like structures within these condensates. They find that the condensates exhibit bimodal internal molecular dynamics, with both liquid- and gas-like macromolecular densities, reflecting the contributions of distinct protein and peptide domains. The network-like organization is characterized by spatial inhomogeneities across different length scales, suggesting that condensates formed by multivalent proteins share features with network fluids formed by systems such as patchy or hairy colloids. The study also highlights the importance of multivalence and associative motifs in driving the formation and properties of these condensates, and discusses the implications for the viscoelastic behavior and rheological properties of the condensates.The study investigates the structural organization and dynamics of biomolecular condensates, specifically focusing on the interactions between nucleolar granular components (GCs) and the proteins that form them. Using a combination of small-angle neutron scattering (SANS), fluorescence recovery after photobleaching (FRAP), and coarse-grained molecular dynamics simulations, the researchers provide insights into the spatial inhomogeneities and network-like structures within these condensates. They find that the condensates exhibit bimodal internal molecular dynamics, with both liquid- and gas-like macromolecular densities, reflecting the contributions of distinct protein and peptide domains. The network-like organization is characterized by spatial inhomogeneities across different length scales, suggesting that condensates formed by multivalent proteins share features with network fluids formed by systems such as patchy or hairy colloids. The study also highlights the importance of multivalence and associative motifs in driving the formation and properties of these condensates, and discusses the implications for the viscoelastic behavior and rheological properties of the condensates.