The following 20 Multiple Choice Questions (MCQ) are based on
Chapter 2: Cell: The Building Block of Life from the NCERT Class 9
Science textbook Exploration . Each question has four options - select the
best answer and click to check.
Instructions: Read each question carefully. Choose the most
appropriate option from (a), (b), (c), or (d). Click
Show Answer to reveal the correct answer with explanation.
Multiple Choice Questions
1
What is the basic structural and functional unit of life?
(a) Tissue
(b) Cell
(c) Organ
(d) Organ system
Show Answer ▼
(b) is correct
All organisms are made of cells, the smallest units capable of carrying out life processes.
2
Which organism is unicellular?
(a) Human
(b) Fish
(c) Bacterium
(d) Mango plant
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(c) is correct
A bacterium consists of a single cell; the other organisms are multicellular.
3
Which sequence shows increasing biological organisation?
(a) Organ - tissue - cell - organism
(b) Cell - tissue - organ - organ system
(c) Tissue - cell - organ system - organ
(d) Cell - organ system - tissue - organ
Show Answer ▼
(b) is correct
Similar cells form tissues, tissues form organs and organs cooperate in organ systems.
4
Which instrument first made cells visible to scientists?
(a) Telescope
(b) Microscope
(c) Barometer
(d) Thermometer
Show Answer ▼
(b) is correct
Microscopes extend vision beyond the naked eye and enabled the study of cells.
5
The cell membrane is described as selectively permeable because it:
(a) Allows every substance to pass freely
(b) Controls which substances enter and leave
(c) Is present only in plants
(d) Is made only of cellulose
Show Answer ▼
(b) is correct
It regulates exchange between the cell and its surroundings.
6
What happens to a carrot kept in concentrated salt solution?
(a) It becomes stiffer as water enters
(b) It becomes limp as water leaves its cells
(c) Its cells divide rapidly
(d) Its cell walls dissolve
Show Answer ▼
(b) is correct
Water moves out through cell membranes into the concentrated solution, reducing cell turgidity.
7
Why does a plant cell not burst easily when water enters it?
(a) Its nucleus absorbs all water
(b) Its rigid cell wall resists expansion
(c) It has no cell membrane
(d) Its mitochondria remove water
Show Answer ▼
(b) is correct
The cell wall provides mechanical support and limits excessive expansion.
8
Which feature is present in both bacterial and animal cells?
(a) Membrane-bound nucleus
(b) Mitochondrion
(c) Cell membrane
(d) Golgi complex
Show Answer ▼
(c) is correct
Both have a plasma membrane, though bacteria lack membrane-bound organelles and a true nucleus.
9
A cell with no membrane-bound nucleus is classified as:
(a) Eukaryotic
(b) Prokaryotic
(c) Multicellular
(d) Meristematic
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(b) is correct
Prokaryotic cells have genetic material but no nuclear membrane.
10
Which organelle contains chromosomes and controls many cell activities?
(a) Nucleus
(b) Vacuole
(c) Lysosome
(d) Ribosome
Show Answer ▼
(a) is correct
The nucleus contains genetic material organised into chromosomes and coordinates cell functions.
11
Which organelle is the main site of protein synthesis?
(a) Ribosome
(b) Golgi complex
(c) Vacuole
(d) Chromoplast
Show Answer ▼
(a) is correct
Ribosomes assemble proteins from amino acids.
12
Which organelle supplies usable energy for many cellular activities?
(a) Lysosome
(b) Mitochondrion
(c) Cell wall
(d) Chromoplast
Show Answer ▼
(b) is correct
Mitochondria release energy from food through cellular respiration.
13
Which structure modifies, packages and dispatches cell products?
(a) Golgi complex
(b) Nucleoid
(c) Cell wall
(d) Centromere
Show Answer ▼
(a) is correct
The Golgi complex processes and packages materials received from the endoplasmic reticulum.
14
Which organelle contains digestive enzymes that break down wastes and foreign material?
(a) Lysosome
(b) Ribosome
(c) Chloroplast
(d) Nucleus
Show Answer ▼
(a) is correct
Lysosomes carry enzymes for intracellular digestion.
15
Which plastid contains chlorophyll and performs photosynthesis?
(a) Leucoplast
(b) Chromoplast
(c) Chloroplast
(d) Vacuole
Show Answer ▼
(c) is correct
Chloroplasts trap light energy through chlorophyll.
16
A large central vacuole in a plant cell mainly helps with:
(a) Protein synthesis only
(b) Storage and maintenance of turgidity
(c) Chromosome formation
(d) Cell division only
Show Answer ▼
(b) is correct
Cell sap in the vacuole stores materials and helps keep the cell firm.
17
Which type of cell division produces two genetically similar daughter cells for growth and repair?
(a) Meiosis
(b) Mitosis
(c) Fertilisation
(d) Osmosis
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(b) is correct
Mitosis maintains chromosome number and supports growth and tissue repair.
18
Why is meiosis important in sexual reproduction?
(a) It doubles chromosome number in gametes
(b) It halves chromosome number in gametes
(c) It produces identical body cells
(d) It prevents genetic variation
Show Answer ▼
(b) is correct
Halving the chromosome number allows fertilisation to restore the normal number.
19
Which statement is part of cell theory?
(a) Cells arise spontaneously from non-living matter
(b) All cells arise from pre-existing cells
(c) Only animals are made of cells
(d) Cells exist only in tissues
Show Answer ▼
(b) is correct
Cell theory states that organisms are made of cells and new cells come from existing cells.
20
Uncontrolled cell division may result in:
(a) Osmosis
(b) A tumour
(c) Photosynthesis
(d) Diffusion only
Show Answer ▼
(b) is correct
Loss of normal control over cell division can produce an abnormal mass of cells called a tumour.
