Name____________________________________ Score:_______________________ Choose the best answer for the following questions, then explain why the answer you choose is correct. Each question is worth 4 pts. 1. How would insulin be produced in the secretory pathway? a. Constitutive secretion d. Regulated secretion b. In the Domesticated Pathway e. None of the above c. In the Endocytic Pathway _______________________________________________________________ _______________________________________________________________ 2. Vesicles travel throughout the cell along which cellular structure(s)? a. Cytoplasm c. Endoplasmic Reticulum b. Plasma Membrane d. Microtubules & Microfilaments _______________________________________________________________ _______________________________________________________________ 3. Signal Peptides are important to secretory proteins because: a. They direct proteins into the ER Membrane b. They cleave the pre-protein sequence to form a mature protein c. They direct proteins to their proper cellular destinations d. They direct proteins into the ER lumen _______________________________________________________________ _______________________________________________________________ 4. Stop-Transfer sequences are important to proteins because: a. They insert proteins into the ER Membrane b. They cleave the pre-protein sequence to form a mature protein c. They direct proteins to their proper cellular destinations d. They direct proteins into the ER lumen ______________________________________________________________________________________________ ______________________________________________________________________________________________ 5. Clatherin-coated vesicles direct cellular cargo to which of the following: a. Golgi c. Endoplasmic Reticulum b. Lysosomes d. Plasma Membrane ______________________________________________________________________________________________ ______________________________________________________________________________________________ 6. Fuzzy-coated vesicles direct cellular cargo to which of the following: a. Golgi c. Endoplasmic Reticulum b. Lysosomes d. Plasma Membrane ______________________________________________________________________________________________ ______________________________________________________________________________________________ 7. Which of the following peptides would be a candidate for N-glycosylation? a. Ala-Ser-Asp-Met-Pro-Val c. Lys(OH)-Pro-Ser-Phe-Thr-Arg b. Lys-Ser-Pro-Thr-Met-Ala d. Lys-Pro-Asn-Arg-Thr-Pro c. Asp-Pro-Ser-Ala-Val-Thr ______________________________________________________________________________________________ ______________________________________________________________________________________________ 8. Which type of glycosylation occurs in the Golgi? a. N-glycosylation c. O-glycosylation b. Both d. Neither ______________________________________________________________________________________________ ______________________________________________________________________________________________ 9. Which of the following peptides would have the most potential for Oglycosylation? a. Ala-Ser-Asp-Met-Pro-Val c. Lys(OH)-Pro-Ser-Phe-Thr-Arg b. Lys-Ser-Pro-Thr-Met-Ala d. Lys-Pro-Asn-Arg-Thr-Pro c. Asp-Pro-Val-Ala-Val-Thr ______________________________________________________________________________________________ ______________________________________________________________________________________________ 10. Which product synthesized by Smooth ER is least desirable? a. Sterols c. Benzopyrenes b. Carbohydrates d. Oxygen-rich by-products ______________________________________________________________________________________________ ______________________________________________________________________________________________ 11. Which post-translational process separates discriminate and nondiscriminate cargo? a. Glycosylation of protreins with mannose sugars in the Golgi b. Cleaving Zymogens into active peptides c. Storing proteins in fuzzy-coated vesicles d. Protein folding ______________________________________________________________________________________________ _____________________________________________________________________________________________ 12. Which is NOT involved in the proper folding of proteins in the ER? a. Glycosyltransferases d. Calnexin b. Protein-Disulfide Isomerases e. Protein disulfide isomerase c. Glycosyltransferases (GT) ______________________________________________________________________________________________ _____________________________________________________________________________________________ 13. Which protein sequence is a candidate to be a membrane protein? a. Ala-Ser-Asp-Met-Pro-Val d. Lys(OH)-Pro-Ser-Phe-Thr-Arg b. Lys-Lys-Pro-Thr-Met-Ala e. Lys-Pro-Asn-Arg-Thr-Pro c. Asp-Pro-Ser-Ala-Val-Thr ______________________________________________________________________________________________ _____________________________________________________________________________________________ 14. What is the function of IgpA and IgpB proteins in lysosomal membranes? a. They maintain a low pH in Lysosomes b. They prevent degredation of Lysosomal Membrane c. They are proton-ATPase pumps d. They transport lysosomal enzymes into the Lysosome ______________________________________________________________________________________________ _____________________________________________________________________________________________ 15. Which is NOT part of the Endomembrane System? a. Golgi Apparatus d. Vacuoles b. Lysosomes e. Peroxisomes c. Endosomes ______________________________________________________________________________________________ _____________________________________________________________________________________________ 16. Proteins are targeted to specific cellular sites to which they function by: a. Sorting Signals d. Signal Peptides b. Coated vesicles c. Signal Recognition Particles ______________________________________________________________________________________________ _____________________________________________________________________________________________ 17. Which is NOT a function of the Smooth ER? a. Detoxification b. Release of glycogen from glucose c. Synthesis of lipids d. Promoting contractions ______________________________________________________________________________________________ _____________________________________________________________________________________________ 18. Which is NOT an ER membrane protein? a. Oligosaccharidetransferases c. Signal Peptidase b. Protein Disulfide Isomerases d. Glycosyltransferases ______________________________________________________________________________________________ _____________________________________________________________________________________________ 19. Glycosyltransferases differ from oligosaccharidetransferases in that Glycosyltransferases add sugars: a. To a nucleotide sugar c. To an oligosaccharide chain b. To proteins d. Lipids ______________________________________________________________________________________________ _____________________________________________________________________________________________ 20. Which is NOT characteristic of the Golgi? a. Consists of interconnected compartments of flatten, dislike cisternae with dilated rims b. Consist of 8 curved cisternae stacked like pancakes c. Associated with vesicles and tubules d. Function in packaging and sorting e. Consist of cis to trans faces ______________________________________________________________________________________________ _____________________________________________________________________________________________ 21. Which of the following does not occur in the cis- and med- Golgi? a. Trimming of proteins b. Cleaving and addition of sugars c. Addition of mannose-6-phosphate d. Binding of Pre-lysosomal enzymes to receptors on Golgi ______________________________________________________________________________________________ _____________________________________________________________________________________________ 22. Which peptide would most likely remain in the ER lumen? a Ala-Ser-Asp-Met-Pro-Val d. Lys(OH)-Pro-Ser-Phe-Thr-Arg b. Lys-Lys-Pro-Thr-Met-Ala e. Lys-Asp-Glu-Leu-Thr-Pro-Ser c. Asp-Pro-Ser-Ala-Val-Thr ______________________________________________________________________________________________ _____________________________________________________________________________________________ 23. Lysosomes are NOT involved in which of the following functions? a. Autophagy c. Intracellular and intercellular digestions b. Fertilization d. Oxidative breakdown of substrates ______________________________________________________________________________________________ _____________________________________________________________________________________________ 24. Which is NOT characteristic of Endosomes? a. They contain proton ATPase pumps b. Late endosomes are located near the plasma membrane c. Its contents are produced in the Biosynthetic-Secretory Pathway d. Lysosomes are the terminal compartment of this pathway ______________________________________________________________________________________________ _____________________________________________________________________________________________ 25. Bulk-phase Endocytosis differ from Receptor-Mediated Endocytosis in that the uptake of materials by Bulk-phase Endocytosis is stimulated by: a. Fluid-filled vesicles b. The binding of molecules to membrane-bound receptors c. Exocytosis d. Shrinkage of the Plasma Membrane ______________________________________________________________________________________________ _____________________________________________________________________________________________