This set of Cell Biology Multiple Choice Questions & Answers (MCQs) focuses on “Types of Biological Molecules”.
1. Proteome is a ____________
a) A precursor of protein
b) Storehouse of proteins
c) An inventory of the total amount of proteins
d) None of the mentioned
Explanation: The entire inventory of proteins that is produced by an organism is known as that organism’s proteome. It may be also applied to the inventory of proteins in a particular tissue or cell. Proteomics is the field of protein biochemistry.
2. Which of the following is not a protein denaturant?
d) Acetic acid
Explanation: Sodium dodecyl sulfate or SDS is a strong denaturant of protein and is used in SDS-PAGE technique. DTT is oftentimes used along with SDS to further denature proteins by reducing their disulfide bonds to allow for better separation of proteins during electrophoresis. Phenol is used as a protein denaturant during isolation of RNA from plants.
3. Which of the following is untrue?
a) Protein folding occurs in Golgi bodies
b) Protein folding is assisted by a protein molecule called Chaperone
c) Transmembrane or organelle proteins contain a signal peptide
d) Proteins are present in cytoplasm and cell organelles of all cells
Explanation: The folding of proteins occurs in the lumen of the Endoplasmic Reticulum (ER). A newly synthesized protein undergoes a series of modifications in the ER with the help of a number of molecular chaperones and folding enzymes that all together assist its proper folding and subsequent release from ER. The majority of ER proteins are dedicated to the folding of proteins. Golgi bodies help in the proper packaging and transport of proteins.
4. RNA does not have the nitrogen base of _______
Explanation: RNA does not have the pyrimidine Thymine and has Uracil instead while DNA has Thymine. In RNA, Adenine binds to Uracil with two hydrogen bonds while in DNA, Adenine binds to Thymine by two hydrogen bonds.
5. Which of the following is functionally the odd one out?
Explanation: micro RNA (miRNA) is a small non-coding RNA that helps in gene silencing. Small interfering RNA (siRNA) helps in gene silencing through the RNA interference pathway. Short hairpin RNA (shRNA) silences target gene via RNA interference. However, small nuclear RNA or snRNA helps in RNA splicing and processing.
6. Which of the following RNA is artificially made?
Explanation: siRNA, snRNA and miRNA are all produced naturally in the cell. Small cytoplasmic RNA (scRNA) is an engineered (artificial) RNA molecule that helps in in-vitro and in-vivo signal transduction.
7. In RNA transcription, which of the following is a part of TBP-associated factor (TAF)?
Explanation: TFIID includes the TBP subunit which binds to the TATA box along with some other proteins, together known as the TBP-associated factors. TFIIB provides a binding site for RNA Polymerase. TFIIF contains a special subunit which is bound to the entering RNA Polymerase. TFIIH contains 10 subunits, 3 of which possess enzymatic activity.
8. Those part of the DNA or gene that contribute to the mRNA product is called _________
b) Intervening sequences
d) Split genes
Explanation: Intervening sequences, also called introns are the portions of DNA excluded during transcription and thus are not there in the mRNA product. Exons are the part of DNA transcribed to form mRNA. The genes with intervening sequences are called split genes.
9. Which of the following disaccharides have beta (1->4) bond?
a) Maltose and Sucrose
b) Maltose and Isomaltose
c) Lactose and Cellobiose
d) Sucrose and Cellobiose
Explanation: Among the disaccharides, sucrose, maltose and isomaltose have alpha(1->4) glycosidic bond. However, lactose, lactulose and sucrose have beta(1->4) glycosidic linkage.
10. An example of polar but uncharged amino acid is ___________
Explanation: Lysine and Arginine are polar and positively charged amino acids. While Aspartate is a polar and negatively charged amino acid. Serine is a polar and uncharged amino acid.
11. Example of a polar amino acid is ____________
Explanation: Glutamine is a polar but non-charged amino acid. Alanine, Valine and Methionine, on the other hand, are non-polar amino acids.
Sanfoundry Global Education & Learning Series – Cell Biology.
To practice all areas of Cell Biology for Interviews, here is complete set of 1000+ Multiple Choice Questions and Answers.