I'm studying for tomorrow's midterm and typing up my notes from class. I don't know if I've mentioned how much I love endoplasmic reticulum and the whole ribosome thing, really.
So a little ribosome is chugging along out in the cytoplasm, and it finds a bit of RNA so it latches on and starts cranking out a protein, and at the N-terminus of that protein, there's a signal sequence that says it's meant for the rough endoplasmic reticulum. Just as the protein starts snaking out of the ribosome, a signal recognition particle comes up behind it and gives it a little cuddle
a creepy little cuddle
saying "Shhhh baby, don't do that. Not here. Not now" and puts its hand over the extrusion site for the protein.
And then they just wait like that in a silent embrace, floating in the cytoplasm, until diffusion takes them to the rough endoplasmic reticulum, where a signal recognition particle receptor binds them and the signal recognition particle shoves the ribosome onto a translocator and says "Do it there!" and then the ribosome finishes pooping the protein directly into the rough endoplasmic reticulum.
That's the most hilarious and disturbing way I've heard cellular processes described. Ever.