NCERT Class 9 Science MCQ | Chapter 2: Cell: The Building Block of Life
Multiple Choice Questions
1. What is the basic level at which life exists?
(A) Tissue
(B) Organ
(C) Cell
(D) Organ system
Answer: (C) Cell
2. Which organisms consist of only one cell?
(A) Multicellular organisms
(B) Unicellular organisms
(C) Organisms with tissues
(D) Organ systems
Answer: (B) Unicellular organisms
3. Which of the following is an example of a unicellular organism mentioned in the chapter?
(A) Fish
(B) Human
(C) Bacteria
(D) Plant
Answer: (C) Bacteria
4. What is the limit of resolution of the human eye given in the chapter?
(A) 1 mm
(B) 0.1 mm
(C) 0.01 mm
(D) 10 mm
Answer: (B) 0.1 mm
5. Which instrument was used by Robert Hooke to observe cells in 1665?
(A) Telescope
(B) Electron microscope
(C) Self-designed microscope
(D) Magnifying glass
Answer: (C) Self-designed microscope
6. What did Robert Hooke observe while examining a thin slice of cork?
(A) Round cells
(B) Box-like compartments
(C) Circular organs
(D) Green structures
Answer: (B) Box-like compartments
7. Who named the small box-like compartments observed in cork as ‘cells’?
(A) Matthias Schleiden
(B) Theodor Schwann
(C) Robert Hooke
(D) Rudolf Virchow
Answer: (C) Robert Hooke
8. Which type of microscope uses a beam of electrons instead of light?
(A) Light microscope
(B) Electron microscope
(C) Simple microscope
(D) Optical microscope
Answer: (B) Electron microscope
9. One millimetre is equal to how many micrometres?
(A) 10 µm
(B) 100 µm
(C) 1000 µm
(D) 10,000 µm
Answer: (C) 1000 µm
10. If the diameter of the visible field is 5000 µm and 25 cells are seen along the diameter, what is the estimated size of one cell?
(A) 100 µm
(B) 200 µm
(C) 250 µm
(D) 500 µm
Answer: (B) 200 µm
11. If both the eyepiece and objective lens of a microscope have a magnifying power of 10X, what is the total magnification?
(A) 10X
(B) 20X
(C) 50X
(D) 100X
Answer: (D) 100X
12. Which of the following is a main feature improved in microscopes over the years?
(A) Weight
(B) Resolution
(C) Temperature
(D) Colour
Answer: (B) Resolution
13. Which structure surrounds a cell and protects its contents?
(A) Cytoplasm
(B) Cell membrane
(C) Nucleus
(D) Ribosome
Answer: (B) Cell membrane
14. The cell membrane is also called the:
(A) Nuclear membrane
(B) Plasma membrane
(C) Cell wall
(D) Cytoplasmic wall
Answer: (B) Plasma membrane
15. What does selectively permeable mean in relation to the cell membrane?
(A) It allows all substances to pass through
(B) It blocks all substances
(C) It allows some substances to pass while blocking others
(D) It allows only proteins to pass
Answer: (C) It allows some substances to pass while blocking others
16. What happened to the potato piece kept in plain water in Activity 2.2?
(A) It shrank
(B) It remained unchanged
(C) It swelled
(D) It dissolved
Answer: (C) It swelled
17. What happened to the potato piece kept in 20 per cent salt or sugar solution?
(A) It swelled
(B) It shrank
(C) It remained unchanged
(D) It dissolved completely
Answer: (B) It shrank
18. What is the movement of water through a selectively permeable membrane called?
(A) Diffusion
(B) Osmosis
(C) Respiration
(D) Filtration
Answer: (B) Osmosis
19. Diffusion is the net movement of particles from:
(A) Lower to higher concentration
(B) Higher to lower concentration
(C) Equal to higher concentration
(D) Lower to equal concentration only
Answer: (B) Higher to lower concentration
20. Which structure provides rigidity and helps plant cells maintain their shape?
(A) Ribosome
(B) Cell wall
(C) Lysosome
(D) Golgi apparatus
Answer: (B) Cell wall
21. The plant cell wall is primarily made of:
(A) Protein
(B) Lipid
(C) Cellulose
(D) DNA
Answer: (C) Cellulose
22. Which of the following cells does not have a cell wall?
(A) Plant cell
(B) Fungal cell
(C) Bacterial cell
(D) Animal cell
Answer: (D) Animal cell
23. Which part of the cell is described as a semi-fluid, jelly-like substance?
(A) Cytoplasm
(B) Cell wall
(C) Nucleus
(D) Cell membrane
Answer: (A) Cytoplasm
24. Which type of cell lacks a well-defined nucleus and membrane-bound organelles?
(A) Eukaryotic cell
(B) Prokaryotic cell
(C) Plant cell
(D) Animal cell
Answer: (B) Prokaryotic cell
25. What is the region containing genetic material in a prokaryotic cell called?
(A) Nucleus
(B) Nucleolus
(C) Nucleoid
(D) Chromosome
Answer: (C) Nucleoid
26. Which type of cells have a well-defined nucleus and membrane-bound organelles?
(A) Prokaryotic cells
(B) Eukaryotic cells
(C) Bacterial cells only
(D) Viral cells
Answer: (B) Eukaryotic cells
27. What is the main function of ribosomes?
(A) Storage of water
(B) Protein synthesis
(C) Digestion of waste
(D) Photosynthesis
Answer: (B) Protein synthesis
28. Which organelle is known as the ‘powerhouse of the cell’?
(A) Golgi apparatus
(B) Ribosome
(C) Mitochondria
(D) Lysosome
Answer: (C) Mitochondria
29. Which organelle modifies, sorts, and packages proteins and lipids?
(A) Golgi apparatus
(B) Ribosome
(C) Nucleus
(D) Vacuole
Answer: (A) Golgi apparatus
30. Which type of cell division produces two genetically identical daughter cells?
(A) Meiosis
(B) Mitosis
(C) Diffusion
(D) Osmosis
Answer: (B) Mitosis
31. Which organelle is mainly involved in protein synthesis and protein secretion and has ribosomes attached to its surface?
(A) Smooth Endoplasmic Reticulum
(B) Rough Endoplasmic Reticulum
(C) Golgi apparatus
(D) Lysosome
Answer: (B) Rough Endoplasmic Reticulum
32. Which type of Endoplasmic Reticulum does not have ribosomes on its surface?
(A) Rough Endoplasmic Reticulum
(B) Smooth Endoplasmic Reticulum
(C) Nuclear Reticulum
(D) Golgi Reticulum
Answer: (B) Smooth Endoplasmic Reticulum
33. Smooth Endoplasmic Reticulum is involved in the synthesis and storage of:
(A) DNA and proteins
(B) Fats and hormones
(C) Cellulose and starch
(D) Water and minerals
Answer: (B) Fats and hormones
34. Which organelle is described as the ‘clean-up system’ of the cell?
(A) Lysosome
(B) Ribosome
(C) Vacuole
(D) Nucleus
Answer: (A) Lysosome
35. Lysosomes contain:
(A) Chlorophyll
(B) Enzymes
(C) Genetic material only
(D) Cellulose
Answer: (B) Enzymes
36. What is the main function of mitochondria?
(A) Packaging proteins
(B) Supplying energy for cellular activities
(C) Storing genetic information
(D) Producing cell wall
Answer: (B) Supplying energy for cellular activities
37. The energy released during cellular respiration in mitochondria is stored in the form of:
(A) DNA
(B) ATP
(C) RNA
(D) Cellulose
Answer: (B) ATP
38. The inner membrane of mitochondria is folded into finger-like projections called:
(A) Stroma
(B) Cristae
(C) Nucleoid
(D) Vesicles
Answer: (B) Cristae
39. Which organelle contains chlorophyll and helps plants synthesise food?
(A) Chloroplast
(B) Lysosome
(C) Ribosome
(D) Golgi apparatus
Answer: (A) Chloroplast
40. Which plastids contain pigments other than chlorophyll and give bright colours to flowers and fruits?
(A) Leucoplasts
(B) Chromoplasts
(C) Chloroplasts
(D) Ribosomes
Answer: (B) Chromoplasts
41. Which plastids are colourless and store food materials such as starch, oils, or proteins?
(A) Chromoplasts
(B) Chloroplasts
(C) Leucoplasts
(D) Mitochondria
Answer: (C) Leucoplasts
42. What is the main function of the large central vacuole in a mature plant cell?
(A) Protein synthesis
(B) Storage and maintenance of cell firmness
(C) DNA synthesis
(D) Packaging of proteins
Answer: (B) Storage and maintenance of cell firmness
43. Which structure contains chromosomes carrying genetic information?
(A) Nucleus
(B) Ribosome
(C) Golgi apparatus
(D) Lysosome
Answer: (A) Nucleus
44. The functional segments of DNA are called:
(A) Chromosomes
(B) Genes
(C) Ribosomes
(D) Chromatin
Answer: (B) Genes
45. What happens to chromatin material when a cell is about to divide?
(A) It disappears
(B) It becomes a cell wall
(C) It gets organised into chromosomes
(D) It changes into ribosomes
Answer: (C) It gets organised into chromosomes
46. Which type of cell division is important for sexual reproduction and creates genetic diversity?
(A) Mitosis
(B) Meiosis
(C) Cell growth
(D) Osmosis
Answer: (B) Meiosis
47. How many daughter cells are produced at the end of meiosis?
(A) One
(B) Two
(C) Three
(D) Four
Answer: (D) Four
48. What happens to the chromosome number during the first division of meiosis?
(A) It doubles
(B) It remains the same
(C) It is reduced to half
(D) It becomes zero
Answer: (C) It is reduced to half
49. Who stated that new cells are formed only from pre-existing cells?
(A) Matthias Schleiden
(B) Theodor Schwann
(C) Rudolf Virchow
(D) Robert Hooke
Answer: (C) Rudolf Virchow
50. According to the classical Cell Theory, which statement is correct?
(A) Only plants are made up of cells.
(B) All living organisms are made up of one or more cells.
(C) Cells arise from non-living matter.
(D) Cells do not perform specific functions.
Answer: (B) All living organisms are made up of one or more cells.
NCERT Class 9 Science MCQ | Chapter 2: Cell: The Building Block of Life
Assertion–Reason Questions
Directions: Choose the correct option:
(A) Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.
(B) Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.
(C) Assertion is true, but Reason is false.
(D) Assertion is false, but Reason is true.
1. Assertion: The cell membrane is selectively permeable.
Reason: It allows some substances to pass through it while blocking others.
Answer: (A)
2. Assertion: A potato piece kept in plain water swells.
Reason: Water moves into the potato cells through the selectively permeable cell membrane.
Answer: (A)
3. Assertion: Plant cells do not shrink completely when placed in a concentrated sugar solution.
Reason: The rigid cell wall helps maintain the shape of plant cells.
Answer: (A)
4. Assertion: Mitosis produces two genetically identical daughter cells.
Reason: Each daughter cell receives the same DNA and the same number of chromosomes as the parent cell.
Answer: (A)
5. Assertion: Meiosis produces four daughter cells with half the number of chromosomes.
Reason: Meiosis consists of two successive cell divisions, resulting in four daughter cells.
Answer: (A)
