7.3: Translation

Prior learning & retrieval practice

S2: The use of molecular visualization software to analyse the structure of eukaryotic ribosomes and a tRNA molecule.

Exercise 3: Review the articles below to visualise the structures of ribosomes and tRNA.

Exercise 4: Watch some additional sources related to the discovery of the structure of ribosomes and the process of translation.

A1: tRNA-activating enzymes illustrate enzyme–substrate specificity and the role of phosphorylation.

Exercise 5: Outline the role of tRNA activating enzymes. How do they illustrate enzyme-substrate specificity? What is the role of phosphorylation?

U1: Initiation of translation involves assembly of the components that carry out the process.

Exercise 6: Outline the initiation stage of translation. Guidance from the syllabus: Examples of start and stop codons are not required.

U2: Synthesis of the polypeptide involves a repeated cycle of events.

Exercise 7: Outline the elongation stage of translation.

U3: Disassembly of the components follows termination of translation.

Exercise 8: Outline the termination stage of translation.

U4: Free ribosomes synthesize proteins for use primarily within the cell.

U5: Bound ribosomes synthesize proteins primarily for secretion or for use in lysosomes.

U6: Translation can occur immediately after transcription in prokaryotes due to the absence of a nuclear membrane.

Exercise 9: List some proteins and their functions that are synthesised on free ribosomes and some on bound ribosomes.

S1: Identification of polysomes in electron micrographs of prokaryotes and eukaryotes.

Exercise 10: What is a polysome? Can you identify them in the pictures below?

NoS: Developments in scientific research follow improvements in computing—the use of computers has enabled scientists to make advances in bioinformatics applications such as locating genes within genomes and identifying conserved sequences. (3.7)

Exercise 11: List some of databases that bioinformatic researchers use to study genetics.