In what order does a charged trna move through the sites of a ribosome?

               During translation process tRNA move from one binding site of ribosome (A site) towards P site.  

Explanation:

                  Ribosome is composed of two sub units, one small and other large. It contain three binding sites for tRNA.  

1. Peptidyl site:

                   It help in holding newly growing polypeptide chain of amino acid.

2. Acceptor site (A site):

                   It help in receiving and holding aminoacyl tRNA which hold amino acid that will be added to polypeptide chain.

3. Exit site (E site):

                   That site where tRNA leave its amino acid.  

The process of translation consists of three main steps:

1. Initiation:

                   In this step mRNA bind to ribosomal sub unit.

2. Elongation:

                    The ribosome read the mRNA by joining with tRNA and help in the formation of polypeptide chain.

3. Termination:

                     When ribosome  reach to stop codon translation stop.  

When the process of translation is started, initiator tRNA carrier of methionine amino acid come and set on start codon (AUG) located in A binding site of larger subunit of ribosome. As ribosome move along mRNA attached tRNA to mRNA is shifted to p site from P to E site.  It should be cleared that prolypeptide chain grow in nitrogen to carboxyl direction.