Final answer:
Aquaporins are channels in cell membranes that allow rapid water movement, distinct from other transport mechanisms like ion channels or carrier proteins.
Step-by-step explanation:
Channels present in the membranes of some cells that allow the rapid movement of water are called aquaporins. These integral transport proteins are specific for water, enabling it to move across the cell membrane much more quickly than it otherwise would by diffusion alone. Aquaporins are a type of channel protein that facilitate water passage by providing a hydrophilic path through the membrane's hydrophobic central layer. This allows water to bypass the nonpolar parts of the plasma membrane, which would significantly slow down or prevent water movement into the cell. While other mechanisms like osmosis can move small amounts of water across the cell membrane, aquaporins are responsible for the vast majority of water transport in cells.
Aquaporins are integral membrane proteins found in the membranes of certain cells that serve as channels for the rapid movement of water. These transport proteins are highly specific to water molecules, facilitating their movement across the cell membrane at a much faster rate than diffusion alone would allow. Aquaporins, functioning as channel proteins, create a hydrophilic path through the hydrophobic central layer of the membrane, providing a specialized route for water transport.
By allowing water to bypass the nonpolar regions of the plasma membrane, aquaporins expedite water movement into and out of cells. While other mechanisms like osmosis contribute to limited water transport, aquaporins play a pivotal role in facilitating the majority of water movement in cells. Their presence is crucial for maintaining water balance, osmoregulation, and various physiological processes in diverse cell types across living organisms.