Cell Structure and Organelles MCQs Quiz 29 Posted on April 6, 2026Author agropublishers 0 1. In the phospholipid bilayer of the plasma membrane, the hydrophilic (polar) heads are oriented ___________ Toward the aqueous environments on both the extracellular and cytoplasmic sides Randomly, with no consistent orientation Away from any aqueous environment, facing only each other Toward the hydrophobic fatty-acid tails in the membrane interior 2. Catalase is a highly efficient antioxidant enzyme found in nearly all aerobic organisms, it detoxifies hydrogen peroxide (H₂O₂) by converting it into _______ Carbon dioxide and water Oxygen and carbon monoxide Water and oxygen Water and Carbon dioxide 3. The cytoplasm of prokaryotes includes _______. Enzymes Cytosol and suspended molecules DNA Ribosomes 4. The DNA of most prokaryotes is typically _______ Linear and multiple Fragmented Linear and single Circular and single 5. Transcription is the biological process of _______ from a DNA template ATP production RNA synthesis DNA duplication Protein synthesis 6. Which organelle is generally absent in prokaryotic cells _______ Cytoplasm Nucleus Cell membrane Ribosome 7. Which statement best describes the role of NADH in cellular ATP production? NADH inhibits ATP synthase to regulate its activity NADH directly phosphorylates ADP to make ATP NADH stores the high-energy phosphate bonds of ATP NADH donates electrons to Complex I of the electron transport chain 8. The cytosol primarily consists of _______ Lipids only Water, ions, and macromolecules Proteins only DNA and RNA only 9. The final electron acceptor in aerobic respiration, essential for ATP production, is _______ NAD⁺ Carbon dioxide Oxygen Glucose 10. The cytoplasm in prokaryotes primarily consists of _______. Nuclear matrix Organelles Cytosol with suspended components Membrane stacks Loading … Question 1 of 10
