The Nucleolus

Within the nucleus are one or more nucleoli. The nucleolus is roughly spherical, and appears as a mass of densely stained granules and fibres under an electron microscope. It consists of nucleolar organizers.  They are specialized regions of some chromosomes with multiple copies of genes for ribosome synthesis, along with a considerable amount of RNA and proteins representing ribosomes in various stages of production. An average, healthy cell can produce up to 10 000 ribosomes per minute.

Back to The Cell

Back to Biology Home Page