So according to my textbook:
RNA is used to create ribosomal RNA (known as rRNA) which is then combined with proteins to form the ribomsomes necessary for protein synthesis.
I'm a bit confused with this statement, as ribosomes are needed to synthesise proteins, but in order to create ribosomes proteins are needed in the first place. How does this work, does the proteins needed for the creation of rRNA come from a different source? Or by synthesising proteins via ribosomes produce more proteins than required to create the ribosomes in the first place?
Also, where are the proteins synthesised? On cytoplasmic ribosomes, or on ribosomes bound to the RER?