Final answer:
Transport proteins in the cell membrane that assist in molecule transfer are known as transport proteins, including channel proteins and carrier proteins.
Step-by-step explanation:
Proteins in the cell membrane that aid in the transport of molecules across the membrane are called transport proteins. These proteins are integral to the cell membrane and function in several ways, including facilitating diffusion and active transport. Specific types of transport proteins include channel proteins and carrier proteins. Channel proteins create hydrophilic pathways that enable polar molecules to bypass the cell membrane's hydrophobic core, thereby allowing substances like water and ions to diffuse quickly. Aquaporins are an example of channel proteins that specifically facilitate rapid water transport across the membrane. On the other hand, carrier proteins bind to molecules and change shape to transport the substance across the membrane. These proteins operate based on concentration gradients and can become saturated when all binding sites are occupied, reaching a maximum rate of transport.