Aquaporins are protein molecules embedded in the phospholipid bilayer of some cells. They transport water across the cell membrane.
A certain amount of water can cross the phospholipid bilayer of the membrane, but aquaporins considerably increase the rate of passage of water.
One type of cell in which aquaporins are found is in the epithelium of the human kidney, in the distal and collecting tubules. The antidiuretic hormone (ADH) stimulates epithelial cells to incorporate aquaporins into their membranes, increasing the uptake of water from the tubule into the cells, and therefore increasing the reabsorption of water into the body.
Aquaporins are also important in plant cells, facilitating the symplastic movement of water through the plant, i.e. the movement of water from cell to cell via cytoplasm.
As the name suggests, they're proteins that transport water in and out of the cell, and the do so selectively (meaning a random hydrogen ion won't be meandering through the protein). They actually regulate the flow of water.
If you're studying up on aquaporins and membranes, I'm guessing you know that water can be diffused into or out of the cell. But larger amounts of water travel through aquaporins.
Some aquaporins (aquaglyceroporins) also transfer the solutes in water, solutes that are relatively small (small being a couple of carbons, maybe 6-ish?) and uncharged, though it largely depends on the size of the aquaporin. Examples of solutes include, carbon dioxide, ammonia, urea (the first organic compound synthesized by man, and yes, a compound found in urine), and, as the name suggests, glycerol.
Aquaporins selectively conduct water molecules in and out of cells.
plasma membrane allows water to enter animal cell
Protein channels known as aquaporins allow water molecules and other water-soluble materials to pass through the cell membrane via passive transport. Aquaporins form water channels that regulate the flow of water across the membrane, facilitating the movement of essential molecules into the cell.
I assume you mean contractile vacuole.There are filaments and coat proteins that surround this vacuole and squeeze the water out of the cell by ATP powered contraction. The cell has a semipermeable membrane that water can pass through and also aquaporins to facilitate water's exit from the cell.
they pull the cell membrane in
These special structures are called protein gates or protein channels. Water is able to diffuse through the cell membrane since it is a small molecule. However, there are channels called aquaporins that allow water to enter the cell. A glucose molecule cannot just diffuse into a cell. There are glucose channels on the surface of the cell membrane that bind glucose molecules and allow them to enter the cell.
Channel proteins.
Aquaporins are protein molecules embedded in the phospholipid bilayer (cell membrane ) of some cells. They transport water across the cell membrane.
Aquaporins
plasma membrane allows water to enter animal cell
it moves through aquaporins in the membrane.
Aquaporins
The movement of water in and out of cells is regulated by aquaporins, which are specialized water channel proteins embedded in the cell membrane. Aquaporins facilitate the rapid movement of water molecules across the membrane, allowing cells to maintain proper water balance and osmotic regulation.
Water may move through membrane pores constructed by transmembrane proteins called aquaporins. These proteins facilitate the transport of water molecules across cell membranes, allowing water to move in and out of cells rapidly and efficiently.
Protein channels known as aquaporins allow water molecules and other water-soluble materials to pass through the cell membrane via passive transport. Aquaporins form water channels that regulate the flow of water across the membrane, facilitating the movement of essential molecules into the cell.
Well, water by itself cannot diffuse into the cell easily, because of its polarity. The cell membrane ultimately determines how much water goes in and out of the cell by aquaporins and other channel proteins. Remember, the membrane is selectively permeable.
Water passes quickly through cell membranes because of the presence of aquaporins, which are specialized protein channels that facilitate the passage of water molecules. Aquaporins ensure fast and selective movement of water into and out of cells, maintaining cellular hydration and osmotic balance efficiently.
Aquaporins are specialized proteins that facilitate the movement of water molecules across cell membranes. They form channels for water to pass through while preventing the passage of ions and other molecules. Aquaporins play a crucial role in maintaining the water balance within cells and tissues.