Exam 8: Cytoplasmic Membrane Systems: Structure, function, and Membrane Trafficking

A cellular phenomenon called RNA interference is a process in which cells produce small RNAs called _______ that bind to specific mRNAs and inhibit the translation of these mRNAs into proteins.

Which of the following is a function associated with the smooth endoplasmic reticulum in at least some cells?

Late endosomes are also referred to as _______.

The process of membrane fusion and subsequent content discharge is called ______ and is usually triggered by a release of ______.

Lysosomal enzymes are transported from the TGN in vesicles coated with what protein?

How many mitochondrial subcompartments exist into which proteins can be delivered?

What is responsible for the deficiency in I-cell disease patients in which the lysosomal enzymes do not carry the normal mannose phosphate residues that target them to lysosomes?

Typically,receptors for hormones or growth factors are destroyed during endocytosis,leading to a reduction in the cell's sensitivity to further stimulation by that particular hormone or growth factor.This is a mechanism by which cells regulate their ability to respond to extracellular messengers.What is it called?

How do early endosomes mature into late endosomes? How is this population of vesicles formed? What name is often given to late endosomes because of the population of vesicles located inside the endosome?

Where are misfolded secretory proteins eventually destroyed?

What would happen to the movement of vesicles toward their eventual target if a microtubule inhibitor like colchicine were added to the cells?

What are the recognition signals for lysosomal enzymes that allow them to be localized correctly in lysosomes?

Which model of Golgi complex formation suggests that the cisternae of a Golgi stack remain in place as stable compartments held together by a protein scaffold,while the cargo is shuttled through the Golgi via vesicles that bud from one compartment and fuse with a neighboring one?

Why are yeast cells often used to study eukaryotic gene mutations affecting secretion and other cytomembrane processes?

Where in the Golgi complex does most protein sorting occur?

What is usually the retrieval signal for ER integral membrane proteins,like the SRP receptor?

With what structure is the RER often seen to be continuous,as seen by its association with ribosomes?

Once the digestive process in an autophagolysosome is completed,the organelle is called a(n)_____.If its contents are not eliminated from the cell by exocytosis and are instead retained within the cytoplasm indefinitely,it is called a(n)_______.

Which of the following is a difference between the coats of COPII- and clathrin-coated vesicles?

Which GTP-binding protein is associated with clathrin-coated vesicles and helps to initiate the formation of the coat?