Question

The ER signal sequence on a growing polypeptide chain is recognized by a signal-recognition particle (SRP) in the cytosol. What does this interaction accomplish? It cleaves the ER signal sequence from the polypeptide chain. It cleaves the ER signal sequence from the polypeptide chain. It guides the ribosome and its polypeptide to the ER. It releases the polypeptide chain from the ribosome. It speeds the synthesis of the polypeptide chain. Which of the following choices reflects the appropriate order of locations through which a protein destined for the plasma membrane travels? lysosome to endosome to plasma membrane ER to endosome to plasma membrane Golgi to lysosome to plasma membrane OER to Golgi to plasma membrane

Answer 1

when a signal recognition particle recognises ER signal sequence , it guides the ribosome and its growing polypeptide to ER. When ER signal sequence emerges from the ribosome they are recognised by signal recognition particles(SRP). SRP binds to both ribosomes and signal sequence. This binding stop translation and this Complex is targetted to receptors present on endoplasmic reticulum (ER).

Appropriate order of locations through which a protein targetted to ER travels is ER $\rightarrow$ Golgi$\rightarrow$Plasma membrane