I was think about buying a 1999-2005 Silver Pf69 Ultra Cameo State Quarters in either Pcgs or Ngc. I was wondering what grading service is the best out of...
There are two different locations where ribosomes can be found in a  cell. These two locations are suspended in the cytosol and attached  to the endoplasmic reticulum.
Ribosomes are found in the cytoplasm of a cell. They are either free floating or bound to the endoplasmic reticulum. Groups of ribosomes stuck together are called polysomes. Most cells contain thousands of ribosomes, while a few specialized cells contain millions. Brain cells and the cells of the pancreas contain large concentrations of ribosomes since they produce a large amount of protein. slide 2 of 6. The Structure of Ribosomes Although ribosomes are called organelles, they don't have a membrane that holds the contents of the ribosome in one cohesive structure. Ribosomes are composed of ribosomal RNA (rRNA) and protein. Sixty percent of the structure is rRNA and 40 percent is protein. There are two subunits: a large subunit and a small subunit. They are labeled as 60s and 40s after the Svedberg values. The subunits of ribosomes are produced in the nucleolus, which is located in the nucleus of the cell. Ribosomal proteins enter the nucleolus and combine with four rRNA strands to produce the two subunits. The subunits leave the nucleus through the nuclear pores and combine in the cytoplasm.