Question

1- How is protein made from mRNA? What raw materials must be present for this process to occur? Why is it important for translation that ribosomes contain three sites for tRNA and not just one?

2-Why can transcription and translation be stimulatenous in prokaryotes but not in eukaryotes?

Answer 1

From the double stranded DNA, mRNA is formed in to the process of transcription. The mRNA has all the information regarding which protein Is being formed. In the translation step, at ribosomes, the mRNA synthesized amino acid sequences with the help of tRNA.

Amin acid synthesis is occurred in cytoplasm at ribosome. tRNA which transfer amino acid. Mature RNA, larger and smaller sub units of ribosome and tRNA are major row Material required for the process of translation.

  

Ribosomes have three specific functional site present for processing of tRNA.

A-site: amino acyle tRNA is bind to the acceptor site

P-site: the peptidyl site, hold the growing peptide chain at the right position.

E-site: it is an exit site. tRNA leaves the ribosome.

It is important to have three site for the processing of tRNA because tRNA has to add amino acid always at carboxyl end. Three site on ribosome alway maintain sequential binding of tRNA from A-P-E.

Prokaryotic transcription and translation occurred simultaneously because both the process occurred in cytoplasm. Prokaryotic cell does not have any membrane bounded nucleus. In contrast, it is not possible in eukaryote. Because the process of transcription is completed in the nucleus whereas the process of translation is completed in cytoplasm at ribosome.