ribosomes

A ribosome is a component of cells that assembles the twenty specific amino acid molecules to form the particular protein molecule determined by the nucleotide sequence of an RNA molecule.[1] One of the central tenets of biology, often referred to as the central dogma of molecular biology, is that DNA is used to make RNA, which is used to make proteins. The DNA sequence in genes is copied into a messenger RNA (mRNA). Ribosomes then read the information in this mRNA and use it to create proteins. This process is known as translation; the ribosome translates the genetic information from the RNA into proteins. Ribosomes do this by binding to an mRNA and using it as a template for determining the correct sequence of amino acids in a particular protein. The amino acids are attached to transfer RNA (tRNA) molecules, which enter one part of the ribosome and bind to the messenger RNA sequence. The attached amino acids are then joined together by another part of the ribosome. The ribosome moves along the mRNA, "reading" its sequence and producing a corresponding chain of amino acids. Ribosomes are made from complexes of RNAs and proteins called ribonucleoproteins. Ribosomes are divided into two subunits. The smaller subunit binds to the mRNA, while the larger subunit binds to the tRNA and the amino acids. When a ribosome finishes reading a mRNA, these two subunits split apart. Ribosomes have been classified as ribozymes, because the ribosomal RNA seems to be most important for the peptidyl transferase activity that links amino acids together. source: http://en.wikipedia.org/wiki/Ribosome

http://sig.uw.edu/fma#Ribosome

http://sig.uw.edu/fma#Ribosome

http://onto.eva.mpg.de/ontologies/gfo-bio.owl#Anatomical_part