Final answer:
Water affects van der Waals forces by forming a hydration shell around proteins, weakening the interactions between protein molecules, and thus influencing their three-dimensional structure which is crucial for proper function.
Step-by-step explanation:
The effect of water on van der Waals forces in relation to proteins involves the formation of a hydration shell around the protein molecules. This hydration shell is formed because water molecules are polar and they tend to surround charged and polar molecules such as proteins, thus introducing a separation between protein molecules. This acts to weaken the van der Waals interactions between protein molecules. Therefore, the correct answer to the question is B) Water forms a hydration shell, weakening van der Waals forces between proteins.
Van der Waals forces occur due to temporary partial charges that result from fluctuations in the electron density around an atom. These forces contribute to the tertiary and quaternary structures of proteins by facilitating weak interactions between molecules when they are in very close proximity.
Water, through the formation of its hydration shell, affects these interactions by separating protein molecules, which diminishes the ability of the proteins to interact via van der Waals forces, thus influencing their three-dimensional structure. It is crucial for this structure to be maintained in order for proteins to function properly within biological systems.