What types of RNA
in a living cell there are three types of RNA: ribosomal, transport and information (matrix) ribonucleic acid.They all differ in structure, molecular size, location in the cell and the functions they perform.
What characterizes the ribosomal RNA (rRNA)
ribosomal RNA make up 85% of total cell RNA.They are synthesized in the nucleolus.Ribosomal RNA is a structural component of the ribosome, and are directly involved in protein biosynthesis. Ribosomes - it organelles cell consisting of four rRNA and several dozen proteins.Their main function - protein synthesis.
Why transfer RNA
transfer RNA (tRNA) - the smallest size ribonucleic acid cells.They make up 10% of all cellular RNA.Transport RNA produced in the nucleus DNA and then transferred int
o the cytoplasm.Each tRNA carries certain amino acids to the ribosomes, where they are joined by peptide bonds in a particular sequence, given messenger RNA.
The RNA molecule transport, there are two active sites: triplet anticodon and acceptor end.Acceptor end - a "landing pad" for amino acids.The anticodon at the other end of the molecule is a triplet of nucleotides complementary to the corresponding mRNA codon. Each amino acid corresponds to a sequence of three nucleotides - triplet.Nucleotide - a monomer nucleic acid consisting of a phosphate group, a pentose and a nitrogenous base.
anticodon tRNA is different for transporting different amino acids.The triplet is encoded information of that amino acid which carries a given molecule.
Where synthesize messenger RNA, and what their role
Information, or messenger RNA (mRNA, mRNA) synthesized at the site of one of the two strands of DNA by an enzyme called RNA polymerase.They make up 5% of cell RNA.The sequence of the nitrogenous bases of mRNA strictly complementary base sequence region of DNA: adenine, uracil DNA corresponding mRNA thymine - adenine, guanine - cytosine and cytosine - guanine.
Messenger RNA reads the genetic information from the chromosomal DNA and carries it to the ribosomes where the information is realized.The nucleotide sequence of mRNA encoded information about the structure of the protein.
RNA molecules may be in the nucleus, cytoplasm, ribosomes, mitochondria and plastids.Because different types of RNA formed a single functional system, directed by the protein synthesis in the implementation of genetic information.