Packing: Cells are packed with molecules like proteins, carbohydrates, and nucleic acids. These molecules take up a significant amount of space within the cell, leaving little room for just water.
Solutes: The intracellular space contains a higher concentration of dissolved molecules (solutes) compared to the extracellular space. This contributes to a higher density.
Extracellular Matrix: The extracellular space, on the other hand, contains a looser network of connective tissues and fluids like interstitial fluid. This allows for more space between molecules, resulting in a lower density.
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