Cell: The Unit of LifeNEET MCQs with solutions
Cell: The Unit of Life covers cell theory, the prokaryotic cell and every organelle of the eukaryotic cell. It is one of the most important chapters for NEET because its facts — who discovered what, ribosome sizes, membrane models and organelle functions — come back in almost every later Biology chapter.
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- 11 Biology
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- 24 questions
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- 531 questions
- ELITE questions
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- NCERT topics
- 5
Practise 24 questions
Tap an option to check it. Questions from every NCERT topic in this chapter, from easy to hard.
Q1Discovery of Cell
The Latin phrase 'Omnis cellula e cellula' means "every cell from a cell" and was stated by:
Not quite — the answer is B.
Virchow (1855) coined this phrase to express that cells only arise from pre-existing cells. Schleiden and Schwann proposed the structural unity of organisms but did not address cell origin. Brown discovered the nucleus.
Q2Discovery of Cell
While studying plant cells, which scientist first recognized the importance of the nucleus and communicated this to Schwann?
Not quite — the answer is B.
Schleiden observed and emphasized the role of the nucleus in plant cells, and this observation influenced Schwann when they met. Robert Brown had earlier described the nucleus, but it was Schleiden's communication to Schwann that contributed to cell theory development — a frequent NEET confusion point.
Q3Discovery of Cell
Which of the following correctly represents the chronological sequence of major contributions to cell theory?
Not quite — the answer is C.
Hooke (1665) coined 'cell'; Leeuwenhoek (~1674) observed living cells; Schleiden (1838) and Schwann (1839) proposed cell theory; Virchow (1855) added cell lineage. Any other order misplaces a key contributor and is factually wrong.
Q4Prokaryotic vs Eukaryotic
Plasmids are best described as:
Not quite — the answer is B.
Plasmids are small, circular, self-replicating DNA molecules found outside the main chromosome in bacteria. They are extrachromosomal and not membrane-bound. Option A is wrong because plasmids have no membrane. Option C describes eukaryotic nuclear DNA.
Q5Prokaryotic vs Eukaryotic
The glycocalyx forms the outermost layer in many bacteria. Which of the following correctly distinguishes its two forms?
Not quite — the answer is C.
Capsule is firmly attached to the cell wall and provides stronger protection against host defenses including phagocytosis. The slime layer is loosely associated. Option A reverses this distinction — the most common exam trap on this concept.
Q6Prokaryotic vs Eukaryotic
Prokaryotic flagella differ from eukaryotic flagella primarily in:
Not quite — the answer is A.
Prokaryotic flagella are made of flagellin protein and lack the 9+2 axonemal arrangement seen in eukaryotic cilia/flagella. Option B is the key trap — tubulin is the eukaryotic flagella protein; prokaryotic flagella use flagellin.
Q7Prokaryotic vs Eukaryotic
Which of the following best explains why eukaryotic cells are generally larger and more complex than prokaryotic cells?
Not quite — the answer is D.
Membrane-bound organelles in eukaryotes create specialised compartments for specific functions — this division of labour supports greater size and complexity. Options A and B are factually false; Option C is incorrect as many eukaryotes do have cell walls.
Q8Prokaryotic vs Eukaryotic
In prokaryotes, DNA is:
Not quite — the answer is A.
Prokaryotic DNA is circular, double-stranded, and not associated with histone proteins — it is "naked." Option D is the key trap: prokaryotic DNA does associate with histone-like proteins (HU, H-NS) but NOT true histones — NCERT explicitly states no histones in prokaryotes.
Q9Cell Envelope
The uptake of solid particles by a cell through membrane engulfment is specifically called:
Not quite — the answer is D.
Phagocytosis ('cell eating') involves engulfment of solid particles (bacteria, debris) via pseudopodia. Pinocytosis (Option A) is 'cell drinking' — uptake of liquid droplets. Receptor-mediated endocytosis (Option B) is selective uptake via specific receptors. Exocytosis (Option C) is the reverse process.
Q10Cell Envelope
Glycoproteins on the outer surface of the plasma membrane are essential for:
Not quite — the answer is C.
Glycoproteins on the extracellular face form the glycocalyx and mediate cell-cell recognition, tissue formation, and immune recognition (e.g., blood group antigens, MHC molecules). They are not involved in DNA transcription or phospholipid synthesis.
Q11Cell Envelope
The plasma membrane is described as 'dynamic' because:
Not quite — the answer is D.
The dynamic nature refers to the lateral mobility of phospholipids and many membrane proteins within the bilayer, as established by the fluid mosaic model. The FRAP (fluorescence recovery after photobleaching) experiment demonstrated this mobility. Not all proteins are mobile — some are anchored to the cytoskeleton.
Q12Cell Envelope
Cholesterol in animal cell membranes primarily:
Not quite — the answer is B.
Cholesterol tucks between phospholipid tails and modulates fluidity — it prevents excessive fluidity at high temperatures and excessive rigidity at low temperatures. It does not replace phospholipids (Option A) or store genetic material (Option D).
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Get RankUp on Google PlayQ13Cell Organelles
Mitochondria are referred to as the 'powerhouse of the cell' because they:
Not quite — the answer is A.
Mitochondria carry out aerobic respiration — oxidative phosphorylation via the electron transport chain and ATP synthase produces the bulk of cellular ATP. The proton gradient across the inner mitochondrial membrane drives ATP synthesis via F₀F₁ ATP synthase.
Q14Cell Organelles
The mature plant cell has a large central vacuole that may occupy what proportion of the cell's volume?
Not quite — the answer is D.
NCERT states the central vacuole in mature plant cells can occupy up to 90% of the cell volume, pushing the cytoplasm and organelles to a thin peripheral layer. This is a direct NCERT factual point frequently tested.
Q15Cell Organelles
Which of the following is the correct set of acid hydrolases found in lysosomes?
Not quite — the answer is C.
Lysosomes contain acid hydrolases — lipases, proteases, carbohydrases (glycosidases), and nucleases — all optimally active at pH ~4.5–5. Option B is the ELITE trap: these are digestive enzymes but are secreted into the gut lumen, not lysosomal enzymes.
Q16Cell Organelles
Formation of primary lysosomes in animal cells primarily involves which organelle?
Not quite — the answer is A.
Primary lysosomes form when the Golgi packages acid hydrolases (synthesized on RER) into membrane vesicles. The enzymes arrive at Golgi via RER → transport vesicle route, and Golgi buds off the primary lysosome.
Q17Cell Organelles
The sedimentation coefficient of the eukaryotic ribosome and its subunits are:
Not quite — the answer is B.
Eukaryotic ribosomes are 80S, composed of a large 60S and small 40S subunit. Prokaryotic ribosomes are 70S (50S + 30S). Options C and D mix up subunit sizes between the two types — a classic NEET numerical trap.
Q18Cell Organelles
The RER appears rough due to the presence of:
Not quite — the answer is A.
Ribosomes studded on the cytoplasmic face of RER membranes give it its characteristic rough appearance. These ribosomes are the site of synthesis of proteins destined for secretion or membrane insertion.
Q19Cell Organelles
Ribosomes present in chloroplasts of eukaryotic plant cells are:
Not quite — the answer is B.
Chloroplast ribosomes are 70S (30S + 50S subunits), like prokaryotic ribosomes — consistent with the endosymbiotic theory that chloroplasts evolved from ancient cyanobacteria. Option A is the trap for students who overgeneralize "eukaryote = 80S."
Q20Cell Organelles
Proteins synthesized on RER ribosomes are transported to the Golgi apparatus via:
Not quite — the answer is D.
Transport vesicles (COPII-coated) bud from the ER and fuse with the cis face of Golgi. Option C is a trap — cytoskeleton guides vesicle movement but does not itself transfer proteins.
Q21Nucleus
A chromatid is best defined as:
Not quite — the answer is D.
After DNA replication, each chromosome consists of two sister chromatids joined at the centromere. Option B (haploid genome) confuses chromatid with chromosome set — a common conceptual error in NEET.
Q22Nucleus
Which of the following cells is correctly identified as anucleate in its mature functional state?
Not quite — the answer is D.
Mature mammalian RBCs eject their nucleus during maturation to maximise haemoglobin-carrying capacity. Neurons, osteocytes, and guard cells all retain their nucleus. Option A (neurons) is the most common NEET trap — they are post-mitotic but not anucleate.
Q23Nucleus
Sieve tube elements in phloem are characterised by:
Not quite — the answer is A.
Mature sieve tube elements lose their nucleus (and tonoplast, ribosomes) yet remain alive — metabolically supported by companion cells. Option C is wrong because mitochondria and some ER persist. This is an elite NCERT trap: living but anucleate.
Q24Nucleus
Euchromatin, compared to heterochromatin, is characterised by being:
Not quite — the answer is B.
Euchromatin is loosely packed, stains lightly, and contains actively transcribed genes. Option A describes heterochromatin. Option C is partially true for constitutive heterochromatin, not euchromatin — a common NEET trap.
ELITE question · AIR under 50 level
This chapter has 50 ELITE questions for students aiming at the very top. They are only in the app.
Unlock ELITE questions in the appCell facts to remember
Quick revision: most questions in this chapter test these facts.
| Topic | Key fact |
|---|---|
| Cell theory | Schleiden (1838) and Schwann (1839); Rudolf Virchow (1855): omnis cellula-e cellula |
| First live cell seen | Anton von Leeuwenhoek; Robert Brown later discovered the nucleus |
| Cell sizes | Mycoplasma about 0.3 µm (smallest); bacteria 3–5 µm; ostrich egg is the largest isolated single cell |
| Prokaryotic cell | No membrane-bound organelles; naked circular DNA; plasmids; 70S ribosomes; mesosomes |
| Glycocalyx | Capsule (tough, firmly attached) or slime layer (loose) |
| Fluid mosaic model | Singer and Nicolson (1972); lipids and proteins move laterally |
| Golgi apparatus | Camillo Golgi (1898); cis (forming) and trans (maturing) faces; forms glycoproteins and glycolipids |
| Lysosomes | Formed by the Golgi; acid hydrolases — lipases, proteases, carbohydrases, nucleases |
| Vacuole | Up to 90% of a plant cell's volume; bounded by the tonoplast |
| Mitochondria | Double membrane; cristae; matrix with circular DNA and 70S ribosomes; site of aerobic respiration |
| Plastids | Chloroplasts, chromoplasts, leucoplasts (amyloplasts, elaioplasts, aleuroplasts) |
| Ribosomes | Discovered by George Palade (1953); eukaryotic 80S (60S + 40S), prokaryotic 70S (50S + 30S) |
| Cilia and flagella | 9 + 2 arrangement of microtubules in the axoneme |
| Centrioles | Cartwheel of nine triplet microtubules |
| Chromosomes by centromere | Metacentric, sub-metacentric, acrocentric, telocentric |
What the app covers in this chapter
531 questions in total, each with a detailed explanation.
| Discovery of Cell | 40 |
| Prokaryotic vs Eukaryotic | 60 |
| Cell Envelope | 61 |
| Cell Organelles | 121 |
| Nucleus | 59 |
| Mixed practice and chapter tests | 190 |
Questions students ask
Is Cell: The Unit of Life important for NEET?
Yes. It is a foundation chapter — its facts on organelles, ribosomes and membranes are used again in cell division, biomolecules, genetics and physiology. Questions are direct and NCERT-based.
Which topics should I revise first?
Start with the prokaryotic versus eukaryotic cell, then the fluid mosaic model and the function of each organelle (use the table on this page), and finish with the nucleus and chromosome types.
How many questions from this chapter are on RankUp?
The RankUp app has 531 questions on Cell: The Unit of Life, including 50 ELITE questions written for students aiming at AIR under 50. Every question has a detailed explanation.
Can I download these questions as a PDF?
Yes. The free PDF on this page has all 24 questions with the answer key and explanations. No signup is needed.
