Multiple choice questions in Cell Biology

1. Protein insertion into the mammalian ER membrane is typically
a. cotranslational c. pretranslational
b. post-translational d. quasitranslational

2. In N-glycosylation of proteins in the ER lumen, sugar(s) are added to the nascent chain at once.
a. 1 c. 7
b. 3 d. 14

3. All of the following proteins interact with exposed amino acids during protein folding in the ER except:
a. BiP c. PDI (protein disulfide isomerase)
b. calnexin and calreticulin d. prolylisomerase

4. Type I membrane proteins have all of the following properties except:
a. cleavable signal sequence c. internal stop-transfer sequence
b. internal signal-anchor sequence d. N-out, C-in topology

5. Proteins that do not fold properly in the ER lumen are degraded in the cytosol by
a. the etiosome c. the proteasome
b. the microsome d. the ribosome

6. Sorting of protein to mitochondrian and chloroplasts is
a. cotranslational c. pretranslational
b. post-translational d. quasitranslational

7. Tom/Tim and Toc/Tic protein complexes are involved in
a. post-receptor recognition events in the cytosolic folding of proteins prior to import into mitochondria or chloroplasts
b. pre-proteasomal steps in tagging aged proteins for degradation
c. protein translocation into mitochondria and chloroplasts, respectively
d. resetting biological clocks following rounds of intense protein synthesis

8. Protein sequences for targeting to mitochondria or chloroplasts are located at
a. the C-terminus of the precursor protein
b. amino acid position 173 in most mitochondrial and chloroplast proteins
c. the N-terminus of the precursor protein
d. At neither terminus.

9. Many peroxisomal matrix proteins are imported as
a. folded proteins
b. nascent chains in the process of completing their elongation
c. protein fragments that are spliced together within the peroxisome
d. unfolded proteins

10. Tom is an abbreviation for _____________________________________________________.


Solution Summary

This solution can prove to be a good practice for cell biology students. This solution has 10 cell biology questions. You can take it as a test and try to solve the questions presented. This will help in testing your knowledge.