What is the difference between pinocytosis and receptor-mediated endocytosis? Which is more specific (picky)?

Well pinocytosis is nonspecific, particles are brought into the cell via invagination, the cell usually just takes in whatever fluids or things are floating around in the EFC while receptor-mediated endocytosis is way more specific. You need to be in a configuration to fit into a receptor in order to be taken in, it doesn't just accept anything that's out there. RME also encases molecules inside of a vesicle that in pinched inward when it's taking things in. It's the difference between having huge, unlocked, unguarded doors in a sea of people, you take in whomever decides to top by or finds themselves there, as a posed to having a locked door with a special password you need to get in, if the PW isn't right no entry.