Cell Structure & Function
Pre Lab Questions
(With Solutions)
2025
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,1. Multiple Choice
Which organelle is the primary site of lipid synthesis and
detoxification of xenobiotics?
A. Rough endoplasmic reticulum
B. Smooth endoplasmic reticulum
C. Golgi apparatus
D. Lysosome
ANS: B
Rationale: Smooth ER lacks ribosomes and contains enzymes for
phospholipid and steroid synthesis, as well as detoxifying reactions.
2. Multiple Choice
Which organelle generates most of the cell’s ATP via oxidative
phosphorylation?
A. Nucleus
B. Lysosome
C. Mitochondrion
D. Peroxisome
ANS: C
Rationale: Mitochondria house the electron transport chain and ATP
synthase, producing ATP by chemiosmosis.
3. Multiple Choice
Which cytoskeletal element primarily resists compressive forces
within the cell?
A. Microtubules
B. Microfilaments
C. Intermediate filaments
D. Actomyosin fibers
ANS: A
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, Rationale: Microtubules are rigid, hollow rods of tubulin that stiffen
the cytoplasm and resist compression.
4. Multiple Choice
Which junction allows direct cytoplasmic exchange of ions and small
molecules between adjacent cells?
A. Tight junction
B. Desmosome
C. Gap junction
D. Hemidesmosome
ANS: C
Rationale: Gap junctions consist of connexin channels that permit
electrical and metabolic coupling.
5. Multiple Choice
In the Golgi apparatus, the “cis” face is responsible for:
A. Sorting outbound secretory vesicles
B. Receiving vesicles from the ER
C. Lipid droplet formation
D. Acid hydrolase activation
ANS: B
Rationale: The cis-Golgi, adjacent to the ER, accepts newly
synthesized proteins via COPII vesicles.
6. Multiple Choice
Which organelle contains acid hydrolases and is responsible for
intracellular digestion?
A. Proteasome
B. Lysosome
C. Endosome
D. Golgi cisterna
ANS: B
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