1. What is autophagy?
A) The process of cell division
B) The process of cellular recycling
C) The process of energy production in cells
D) The process of protein synthesis
Answer: B) The process of cellular recycling
2. Which of the following is NOT involved in autophagy?
A) Lysosomes
B) Mitochondria
C) Ribosomes
D) Autophagosomes
Answer: C) Ribosomes
3. What is the role of autophagosomes in autophagy?
A) They degrade cellular waste
B) They help in the formation of new cells
C) They transport waste materials to the lysosome
D) They produce energy for the cell
Answer: C) They transport waste materials to the lysosome
4. Which organelle is primarily involved in autophagy?
A) Nucleus
B) Endoplasmic reticulum
C) Lysosome
D) Golgi apparatus
Answer: C) Lysosome
5. Which protein complex is crucial for the initiation of autophagy?
A) mTOR complex
B) PKA complex
C) DNA polymerase complex
D) RNA polymerase complex
Answer: A) mTOR complex
6. In autophagy, what happens to the damaged organelles?
A) They are recycled for energy
B) They are broken down and removed
C) They are repaired and reused
D) They accumulate in the cytoplasm
Answer: B) They are broken down and removed
7. What is the name of the double-membraned vesicle that forms during autophagy?
A) Lysosome
B) Autophagosome
C) Phagosome
D) Endosome
Answer: B) Autophagosome
8. Which of the following triggers autophagy in cells?
A) Cellular stress
B) High levels of glucose
C) DNA replication
D) Protein synthesis
Answer: A) Cellular stress
9. What is the ultimate fate of autophagosomes in the process of autophagy?
A) They fuse with the nucleus
B) They release enzymes for digestion
C) They merge with the lysosome for degradation
D) They become part of the cytoplasm
Answer: C) They merge with the lysosome for degradation
10. Which enzyme plays a key role in the degradation of cellular components during autophagy?
A) Amylase
B) Hydrolase
C) Lipase
D) Protease
Answer: B) Hydrolase
11. What type of molecules are typically degraded by autophagy?
A) Lipids and proteins
B) Carbohydrates and proteins
C) Nucleic acids and lipids
D) Proteins, lipids, and damaged organelles
Answer: D) Proteins, lipids, and damaged organelles
12. Which phase of the cell cycle is autophagy most active in?
A) G0 phase
B) G1 phase
C) S phase
D) G2 phase
Answer: A) G0 phase
13. Which protein complex inhibits autophagy under normal nutrient conditions?
A) mTOR complex
B) AMPK complex
C) JNK complex
D) RAS complex
Answer: A) mTOR complex
14. What does the term “selective autophagy” refer to?
A) The random degradation of cellular components
B) The degradation of specific organelles or molecules
C) The recycling of non-functional proteins only
D) The breakdown of cytoplasm
Answer: B) The degradation of specific organelles or molecules
15. Which of the following diseases is linked to defective autophagy?
A) Parkinson’s disease
B) Hypertension
C) Asthma
D) Hepatitis
Answer: A) Parkinson’s disease
16. What is the role of the protein Beclin-1 in autophagy?
A) It promotes the formation of autophagosomes
B) It degrades cellular components
C) It inhibits the fusion of autophagosomes with lysosomes
D) It synthesizes lipids for autophagy
Answer: A) It promotes the formation of autophagosomes
17. Which of the following is an example of autophagic degradation?
A) Breakdown of glucose for energy production
B) Breakdown of worn-out organelles like mitochondria
C) Synthesis of new proteins
D) Transport of nutrients into the cell
Answer: B) Breakdown of worn-out organelles like mitochondria
18. What is the main energy source required for autophagy to function?
A) Oxygen
B) ATP
C) Glucose
D) Lipids
Answer: B) ATP
19. Autophagy can be upregulated by the activation of which protein kinase?
A) AKT kinase
B) AMPK kinase
C) PKA kinase
D) MAPK kinase
Answer: B) AMPK kinase
20. What is the role of the lysosome in autophagy?
A) It produces proteins for degradation
B) It stores energy for the cell
C) It fuses with the autophagosome to degrade its contents
D) It forms new autophagosomes
Answer: C) It fuses with the autophagosome to degrade its contents
21. Which of the following is NOT a step in autophagy?
A) Formation of autophagosome
B) Fusion with lysosome
C) Degradation of cellular components
D) Cellular division
Answer: D) Cellular division
22. What is the role of LC3 in autophagy?
A) It helps in the formation of the autophagosome membrane
B) It degrades proteins
C) It transports proteins to the lysosome
D) It inhibits autophagy
Answer: A) It helps in the formation of the autophagosome membrane
23. Which organelle is selectively degraded through mitophagy?
A) Golgi apparatus
B) Endoplasmic reticulum
C) Mitochondria
D) Ribosomes
Answer: C) Mitochondria
24. How does autophagy contribute to cancer progression?
A) By promoting uncontrolled cell division
B) By inhibiting cell death
C) By enhancing immune responses
D) By increasing the repair of DNA damage
Answer: B) By inhibiting cell death
25. Which of the following cellular processes is regulated by autophagy?
A) Cell metabolism
B) DNA replication
C) Protein synthesis
D) RNA transcription
Answer: A) Cell metabolism
26. What happens to the autophagic process when nutrients are abundant?
A) Autophagy is activated
B) Autophagy is inhibited
C) Autophagy remains constant
D) Autophagy is enhanced by mTOR
Answer: B) Autophagy is inhibited
27. Which of the following is a characteristic of autophagic vesicles?
A) Single-membraned
B) Double-membraned
C) Membrane-bound
D) None of the above
Answer: B) Double-membraned
28. Which of the following diseases is considered a lysosomal storage disorder caused by impaired autophagy?
A) Alzheimer’s disease
B) Tay-Sachs disease
C) Huntington’s disease
D) Diabetes
Answer: B) Tay-Sachs disease
29. What cellular event can activate autophagy during nutrient starvation?
A) Increase in protein synthesis
B) Decrease in cellular ATP levels
C) Cell division
D) Growth factor stimulation
Answer: B) Decrease in cellular ATP levels
30. How does autophagy contribute to cellular quality control?
A) By creating new organelles
B) By eliminating damaged organelles and proteins
C) By promoting cell division
D) By increasing energy production
Answer: B) By eliminating damaged organelles and proteins
