Which one of the following statements about secreted proteins is incorrect? Secreted proteins: are likely to have received N-linked glycosylation in the rough ER. are synthesized on membrane-bound ribosomes, not free cytosolic ribosomes. that are constitutively expressed are exported as they are prepared, as opposed to being released as a response to a signal. cannot be exported into the extracellular space until the vesicle they are in fuses with the plasma membrane. travel directly from the rough endoplasmic reticulum into the trans face of the Golgi Apparatus.