The process involves extension and invagination of the plasma membrane to form small vesicles in pinocytosis (pinocytotic vesicles) or vacuoles in phagocytosis (food vacuoles).
Note the clear vacuoles in the colloid next to the epithelium where the increased activity of the epithelium to produce increased thyroid hormone has led to scalloping out of the colloid.
Finally, plant cells also contain structures known as vacuoles; these are filled with a watery substance which contains dissolved sugars called cell sap.
Vacuoles are often the largest organelle in a plant cell, and when plants do not get enough water, their vacuoles shrink, and the plant begins to wilt.
Vacuoles help cells grow, store proteins and sugars, and often contain colored pigments, so we have them to thank for the pretty pink petals on our roses.
He reasoned that if the backlog of stuff didn’t pile up in the vacuole, the genes that were supposed to send it there had to be the ones that has been turned off.