Properties and characteristics of cells MCQs With Answer

Introduction: Understanding the properties and characteristics of cells is crucial for B.Pharm students studying pharmacology, drug delivery, and cellular responses to therapeutics. This topic covers cell structure, membrane composition, organelles (mitochondria, ER, Golgi, lysosomes, peroxisomes), cytoskeleton, cell signaling, transport mechanisms (diffusion, osmosis, facilitated and active transport), cell division, and differences between prokaryotic and eukaryotic cells. Knowledge of membrane permeability, ion gradients, receptor localization, and cell polarity informs drug targeting and absorption. These core concepts connect molecular pharmacology to physiological outcomes and therapeutic design. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. Which statement best summarizes the cell theory?

• All living organisms are composed of one or more cells.
• Cells arise spontaneously from non-living matter.
• Each cell can live independently outside an organism.
• Organelles function independently of the cell.

Correct Answer: All living organisms are composed of one or more cells.

Q2. The plasma membrane is primarily composed of which structure?

• Peptidoglycan layer
• Phospholipid bilayer with embedded proteins (fluid mosaic model)
• Cellulose microfibrils
• Triphosphate lipid matrix

Correct Answer: Phospholipid bilayer with embedded proteins (fluid mosaic model)

Q3. Which organelle is the main site of ATP production in eukaryotic cells?

• Golgi apparatus
• Mitochondrion
• Smooth endoplasmic reticulum
• Lysosome

Correct Answer: Mitochondrion

Q4. Protein synthesis occurs primarily at which cellular structure?

• Mitochondria
• Ribosome
• Peroxisome
• Golgi apparatus

Correct Answer: Ribosome

Q5. Which organelle is responsible for detoxification and lipid synthesis, lacking ribosomes?

• Rough endoplasmic reticulum
• Smooth endoplasmic reticulum
• Golgi apparatus
• Centrosome

Correct Answer: Smooth endoplasmic reticulum

Q6. Peroxisomes are primarily involved in which function?

• Protein glycosylation
• β‑oxidation of very long chain fatty acids and hydrogen peroxide breakdown
• ATP synthesis through oxidative phosphorylation
• Chromosome segregation during mitosis

Correct Answer: β‑oxidation of very long chain fatty acids and hydrogen peroxide breakdown

Q7. The Golgi apparatus mainly functions to:

• Synthesize DNA
• Modify, sort, and package proteins and lipids for secretion or delivery
• Generate ATP
• Filter cytosolic waste

Correct Answer: Modify, sort, and package proteins and lipids for secretion or delivery

Q8. Microtubules are composed of which protein and participate in what process?

• Actin; muscle contraction
• Keratin; barrier formation
• Tubulin; mitotic spindle formation and intracellular transport
• Myosin; vesicle budding

Correct Answer: Tubulin; mitotic spindle formation and intracellular transport

Q9. Osmosis refers to the movement of:

• Solutes from low to high concentration through a membrane carrier
• Water across a semipermeable membrane from low solute to high solute concentration
• Ions only via ion channels
• Large proteins into lysosomes

Correct Answer: Water across a semipermeable membrane from low solute to high solute concentration

Q10. Facilitated diffusion differs from active transport because facilitated diffusion:

• Requires ATP hydrolysis
• Moves substances against their concentration gradient
• Uses carriers or channels but does not require direct energy input
• Is exclusive to prokaryotic cells

Correct Answer: Uses carriers or channels but does not require direct energy input

Q11. Which process requires ATP directly to move ions across the plasma membrane?

• Simple diffusion
• Facilitated diffusion
• Primary active transport (e.g., Na+/K+ ATPase)
• Osmosis

Correct Answer: Primary active transport (e.g., Na+/K+ ATPase)

Q12. Phagocytosis is best described as:

• Selective receptor-mediated uptake of small molecules
• Cellular uptake of large particles or cells by engulfment
• Fusion of vesicles with the plasma membrane to secrete contents
• Transport of ions through tight junctions

Correct Answer: Cellular uptake of large particles or cells by engulfment

Q13. Exocytosis in secretory cells primarily functions to:

• Internalize nutrients
• Secrete proteins and neurotransmitters by vesicle fusion with the plasma membrane
• Break down cellular waste
• Replicate mitochondrial DNA

Correct Answer: Secrete proteins and neurotransmitters by vesicle fusion with the plasma membrane

Q14. The nucleus contains which of the following key structures for ribosome biogenesis?

• Centrosome
• Nucleolus
• Golgi stacks
• Peroxisomal body

Correct Answer: Nucleolus

Q15. Eukaryotic ribosomes consist of which subunits?

• 30S and 50S
• 40S and 60S
• 20S and 40S
• 10S and 20S

Correct Answer: 40S and 60S

Q16. A defining feature of prokaryotic cells is:

• Membrane-bound nucleus and organelles
• Absence of a true nucleus and membrane-bound organelles
• Presence of multiple linear chromosomes within a nucleus
• Endoplasmic reticulum surrounding DNA

Correct Answer: Absence of a true nucleus and membrane-bound organelles

Q17. Bacterial cell walls are mainly composed of:

• Cellulose
• Chitin
• Peptidoglycan
• Lipopolysaccharide alone

Correct Answer: Peptidoglycan

Q18. The resting membrane potential of many animal cells is primarily maintained by:

• Equilibrium of chloride only
• Na+/K+ ATPase activity and differential ion permeability (mainly K+ leak channels)
• Passive diffusion of glucose
• Endocytosis rate

Correct Answer: Na+/K+ ATPase activity and differential ion permeability (mainly K+ leak channels)

Q19. A typical neuronal resting membrane potential is approximately:

• +40 mV
• 0 mV
• -70 mV
• -300 mV

Correct Answer: -70 mV

Q20. Tight junctions in epithelial cells primarily serve to:

• Anchor cells to the extracellular matrix
• Allow free ion passage between cells
• Create a paracellular barrier to prevent leakage between cells
• Mediate electrical synapses

Correct Answer: Create a paracellular barrier to prevent leakage between cells

Q21. Gap junctions enable cells to:

• Form a waterproof barrier
• Exchange small molecules and ions directly via connexon channels
• Secure cells to the basement membrane
• Digest extracellular pathogens

Correct Answer: Exchange small molecules and ions directly via connexon channels

Q22. Desmosomes are specialized for:

• Electrical coupling
• Strong mechanical adhesion between cells via intermediate filaments
• Selective ion transport
• Protein secretion

Correct Answer: Strong mechanical adhesion between cells via intermediate filaments

Q23. Apical-basal polarity in epithelial cells is important because:

• It randomizes transport across the cell layer
• It enables directional transport and localized receptor placement crucial for absorption and drug targeting
• It prevents cell division
• It dissolves tight junctions

Correct Answer: It enables directional transport and localized receptor placement crucial for absorption and drug targeting

Q24. During which phase of the cell cycle does DNA replication occur?

• G0 phase
• M phase
• S phase
• G2 phase

Correct Answer: S phase

Q25. During mitosis, chromosomes align at the metaphase plate in which stage?

• Prophase
• Metaphase
• Anaphase
• Telophase

Correct Answer: Metaphase

Q26. Apoptosis is characterized by which of the following?

• Uncontrolled cell swelling and lysis
• Caspase activation, DNA fragmentation, and formation of apoptotic bodies
• Immediate inflammation and membrane rupture
• Permanent cell fusion

Correct Answer: Caspase activation, DNA fragmentation, and formation of apoptotic bodies

Q27. Lysosomes are best described as:

• Sites of ATP generation
• Acidic organelles containing hydrolytic enzymes for intracellular digestion
• Ribosome assembly centers
• Primary sites of transcription

Correct Answer: Acidic organelles containing hydrolytic enzymes for intracellular digestion

Q28. For passive membrane permeation of a drug, which property generally increases permeability?

• High ionization at physiological pH
• Large polar surface area
• Non-ionized lipophilic form
• Extensive hydrogen bonding with water

Correct Answer: Non-ionized lipophilic form

Q29. A high surface area-to-volume ratio in cells favors:

• Slower nutrient and waste exchange
• More efficient exchange of materials with the environment
• Increased genomic instability
• Reduced membrane transport capacity

Correct Answer: More efficient exchange of materials with the environment

Q30. The fluid mosaic model explains that membrane proteins:

• Are fixed rigidly and cannot move laterally
• Float in a fluid lipid bilayer and can move laterally, contributing to membrane dynamics
• Are absent from cell membranes
• Form crystalline arrays impermeable to small molecules

Correct Answer: Float in a fluid lipid bilayer and can move laterally, contributing to membrane dynamics

Download