The signal recognition particle (SRP) is a cytoplasmic RNA-protein (ribonucleoprotein) complex whose primary role is to target signal peptide‐bearing proteins to the plasma membrane in prokaryotes and to the endoplasmic reticulum in eukaryotes. In eukaryotic organisms, SRP binds to the signal sequence of the protein when the growing polypeptide chain emerges from the ribosome in the cytoplasm. This binding is key because it results in a slowing of translation, a mechanism known as elongation arrest. Therefore, without a functional SRP, elongation arrest would not occur and proteins would be translated on free ribosomes in the cytoplasm.
This is a part of the nervous that operates involuntarily (you can’t control it) and functions to “turn you on” as part of the fight or flight response.
The parasympathetic is the other big involuntary part that mostly does the opposite functions.
