Which of the following processes allows cells to concentrate material that is present only in very small amounts in the extracellular fluid? Which of the following processes allows cells to concentrate material that is present only in very small amounts in the extracellular fluid? receptor-mediated endocytosis phagocytosis transcytosis pinocytosis

Receptor mediated endocytosis is the process in which some integral membrane proteins, which spans along the width of the plasma membrane, or certain carrier proteins also located in the plasma membrane have the capability of specifically binding to certain solutes. These proteins can capture the required solute present in the extra-cellular fluid, transfer them across the plasma membrane and deposit them to the interior of the cell in the intra-cellular fluid. This way the particular material which is found in low amounts outside the cell can get concentrated inside the cell.
Phagocytosis is the process by which cells, especially the immune cells like macrophage or monocytes, extends their membrane around a foreign body by the formation of finger-like structures called Pseudopodia and engulf the foreign body for the purpose of digestion.
Transcytosis is the process in which certain solutes are transported in vesicles from one cell to another. These solute containing vesicles enters the cell from one side and leaves the cell from the other. This is mostly observed in epithelial cells which absorb nutrients from its apical surface and release the nutrients from its basolateral surface.
Pinocytosis is the process by which large amount of fluid is ingested into the cells by means of vesicles.