And the number of English language learners has increased by 65 percent between 1993 and 2004 compared to barely a 7 percent increase in the total K12 population, according to a 2006 study by the National Clearinghouse for English Language Acquisition.
Exocytosis. Photo by: Alila. Exocytosis is the cellular process in which intracellular vesicles in the cytoplasm fuse with the plasma membrane and release or secrete their contents into the extracellular space. Exocytosis can be constitutive (occurring all the time) or regulated. Constitutive exocytosis is important in transporting proteins like receptors that function in the plasma membrane. Regulated exocytosis is triggered when a cell receives a signal from the outside.
Exocytosis is the process by which cargo-laden transport vesicles move through the cytoplasm to the plasma membrane. Once at the plasma membrane two different things can happen. Sometimes the vesicle can dock and wait for a secretion signal. This happens in calcium-dependent (regulated) exocytosis.