In eukaryotes, ribosomes become associated with endoplasmic reticulum membranes when a signal sequence from the RNA is given.
In the cytoplasm, ribsomal RNA (rRNA), a type of RNA, and protein
combine to form a nucleoprotein called a ribosome. The ribosome serves as
the site and carries the enzymes necessary for protein synthesis. They are
often takes the shape of small round particles attached in the endoplasmic
reticulum. The ribosome attaches itself to m-RNA and provides the stabilizing
structure to hold all substances in position as the protein is synthesized. An example of a eukaryote is the protists. Protists belong to the group eukaryotes (having their DNA enclosed
inside the nucleus). They are not plants, animals or fungi but they act like
one. They can be in general subgroups such as unicellular algae, protozoa and
molds. They thrive in environments with little sunlight.