Question

At least three types of RNA are required for protein synthesis. Compare and contrast mRNA, rRNA, and tRNA by moving the descriptions of their structure and function to the appropriate categories. Some phrases may describe all three types of RNA.

Answer 1

Drawing myself and giving full explanation takes a lot of time because we have read this whole semester of M.Sc. It is well known so that I am compiling required information from the internet. Where ever require, I have explained there. Don't misunderstand me, go through this you will get full idea of your question

All there RNAs coded by different RNA polymerases mRNA (pol ll), rRNA (pol l) and tRNA (pol lll). They may do the different functions, but all are coordinated during protein synthesis. In prokaryotes, 70S ribosomes consist of h 23S, 16S, 5S rRNA molecules but in eukaryotes 28S, 18S, 5.8S and 5S rRNA molecules majorly present. Sometimes rRNA molecules act like enzymes are called as ribozymes.

Messenger RNA (mRNA) carries the genetic information copied from DNA in the form of a series of three-base code “words,” each of which specifies a particular amino acid.

Transfer RNA (tRNA) is the key to deciphering the code words in mRNA. Each type of amino acid has its own type of tRNA, which binds it and carries it to the growing end of a polypeptide chain if the next code word on mRNA calls for it. The correct tRNA with its attached amino acid is selected at each step because each specific tRNA molecule contains a three-base sequence that can base-pair with its complementary code word in the mRNA.

Ribosomal RNA (rRNA) associates with a set of proteins to form ribosomes. These complex structures, which physically move along an mRNA molecule, catalyze the assembly of amino acids into protein chains. They also bind tRNAs and various accessory molecules necessary for protein synthesis. Ribosomes are composed of a large and small subunit, each of which contains its own rRNA molecule or molecules.   

  

Here, the ribosome is moving through mRNA (codons) that were paired with anticodons of tRNA. Actually, the initial aminoacyl-tRNA (met) brought to binds with AUG initiation codon of mRNA, this pairing was be facilitated by Shinydalgano/Kozak (prokaryotes/eukaryotes) sequence present in rRNA. While moving ribosome in 5'-3' direction on mRNA that brings appropriate aminoacyl-tRNA into the ribosomal A-site. Then the amino acid forms a peptide bond with earlier amino acid present in P-site and it would leave the ribosome from P-site. Like that, all the codons of mRNA is recruited by proper amino acid and form the peptide and the elongation is terminated when stop codon reached.

tRNA structure with five different arm

rRNA structure with different subunits

Molecular dogma