Cell Biology Multiple Choice Questions on “Cytoplasmic Membrane Systems – Endomembrane System”.
1. Which of the following together represent an endomembrane system?
A. macromolecules of the cell
B. cell receptors
C. cytoplasmic structures
D. nuclear structures
Answer: C
Clarification: The cytoplasmic organelles of a cell namely endoplasmic reticulum, Golgi complex, lysosomes, vacuoles; together represent the endomembrane system where individual components function as a part of a coordinated unit.
2. Organelles of the endomembrane system are stable and static.
A. True
B. False
Answer: B
Clarification: Organelles of the endomembrane system are dynamic in nature and experience a continuous flux while they perform the regular activities inside the cell.
3. Proteins are synthesized in which of the following organelle of the endomembrane system?
A. Endoplasmic reticulum
B. Golgi complex
C. Lysosomes
D. Vacuoles
Answer: A
Clarification: Proteins are synthesized in the endoplasmic reticulum and then modified in the Golgi complex. From the Golgi complex, the proteins are further transported to different destinations depending upon their function and fate.
4. There are ______ types of secretory activities of a cell.
A. one
B. two
C. three
D. four
Answer: B
Clarification: Secretory activities lead to the discharge of proteins synthesized in the endoplasmic reticulum. There two types of secretory activities of a cell namely constitutive secretion and regulated secretion.
5. In regulated secretion, materials are __________
A. secreted
B. stored
C. degraded
D. aggregated
Answer: B
Clarification: In regulated secretion activities of the cell, materials are stored in membrane bound packages and released only when there is an invoked response.
6. Which type of endomembrane secretion occurs in nerve cells?
A. constitutive
B. regulatory
C. non-continuous
D. intermittent
Answer: B
Clarification: The nerve cells secrete neurotransmitters in response to an extracellular stimulus, the secretion is therefore termed as regulatory secretion.
7. What of the following molecules is not transported through the secretory pathway of endomembrane system?
A. nucleic acids
B. complex polysaccharides
C. proteins
D. lipids
Answer: A
Clarification: In the secretory pathway or the biosynthetic pathway biomolecules like proteins, lipids and complex polysaccharides are transported across the cell.
8. In the endocytic pathway, materials are discharged from the cell.
A. True
B. False
Answer: B
Clarification: Endocytic pathway is the opposite of secretory pathway. In the endocytic pathway materials move from the outer surface of the cell to the cytoplasmic compartments like endosomes and lysosomes.
9. Which of the following biomolecules are contained in the lysosomes?
A. nucleic acids
B. ribonucleic acids
C. proteins
D. polysaccharides
Answer: C
Clarification: The lysosomes play a vital role in digestion and waste removal from the cell. These organelles are composed of soluble proteins that carry out this function.
10. Which type of signals direct the proteins to their appropriate cellular destinations?
A. sorting signals
B. apoptotic signals
C. ubiquitylation
D. degradation signals
Answer: A
Clarification: Sorting signals encoded in amino acid sequence of proteins or in the attached sugar molecules are responsible for directing the proteins to their appropriate cellular destinations.