🧬 Cell – Structure and Functions (Class 8 Science)

Part 3: Q51–Q75

Q51. Which organelle is called the “protein factory of the cell”?

A) Golgi apparatus
B) Ribosome
C) Lysosome
D) Vacuole

✅ Correct Answer: B) Ribosome

Explanation:

• A) Golgi – Packaging.
• B) ✔ Ribosomes synthesize proteins.
• C) Lysosome – Digestion.
• D) Vacuole – Storage.

Q52. Which part of the cell is responsible for providing structural support in plants?

A) Cell wall
B) Nucleus
C) Ribosome
D) Cytoplasm

✅ Correct Answer: A) Cell wall

Explanation:

• A) ✔ Cell wall made of cellulose provides rigidity.
• B, C, D – Do not provide shape/rigidity.

Q53. What is the control center of the cell?

A) Cytoplasm
B) Ribosome
C) Nucleus
D) Lysosome

✅ Correct Answer: C) Nucleus

Explanation:

• A, B, D – Other roles.
• C) ✔ Nucleus contains DNA, directs cell activities.

Q54. The thread-like structures carrying genes are called:

A) Ribosomes
B) Chromosomes
C) Plastids
D) Mitochondria

✅ Correct Answer: B) Chromosomes

Explanation:

• A, C, D – Not genetic material.
• B) ✔ Chromosomes in nucleus carry DNA and genes.

Q55. Which type of plastid stores starch, oil, and protein granules?

A) Chloroplast
B) Chromoplast
C) Leucoplast
D) Mitochondria

✅ Correct Answer: C) Leucoplast

Explanation:

• A) Chloroplast – Photosynthesis.
• B) Chromoplast – Pigments (red/orange).
• C) ✔ Leucoplast stores food (starch, proteins, fats).
• D) Mitochondria – Energy.

Q56. The longest cell in the human body is:

A) Ovum
B) Red blood cell
C) Nerve cell
D) Muscle cell

✅ Correct Answer: C) Nerve cell

Explanation:

• A) Ovum – Largest, not longest.
• B) RBC – Small biconcave cells.
• C) ✔ Nerve cells can be up to 1 m long.
• D) Muscle cells – Long but shorter than nerves.

Q57. Which organelle releases energy in the form of ATP?

A) Mitochondria
B) Chloroplast
C) Ribosome
D) Golgi apparatus

✅ Correct Answer: A) Mitochondria

Explanation:

• A) ✔ Mitochondria break down glucose → release ATP.
• B, C, D – Other functions.

Q58. The jelly-like substance inside a cell that holds organelles is:

A) Cytoplasm
B) Chromatin
C) Vacuole
D) Protoplasm

✅ Correct Answer: A) Cytoplasm

Explanation:

• A) ✔ Cytoplasm surrounds organelles, medium for reactions.
• B) Chromatin – DNA material.
• C) Vacuole – Storage sac.
• D) Protoplasm – Cytoplasm + nucleus.

Q59. The functional unit of heredity is:

A) Chromosome
B) Gene
C) DNA
D) RNA

✅ Correct Answer: B) Gene

Explanation:

• A) Chromosome – Made of genes.
• B) ✔ Gene = basic hereditary unit.
• C) DNA – Chemical basis of genes.
• D) RNA – Protein synthesis helper.

Q60. Which part of the cell is porous and allows exchange of materials?

A) Nuclear membrane
B) Cell membrane
C) Cell wall
D) Cytoplasm

✅ Correct Answer: A) Nuclear membrane

Explanation:

• A) ✔ Nuclear pores allow RNA/protein movement.
• B) Cell membrane – Selectively permeable, but not nuclear.
• C) Cell wall – Fully permeable.
• D) Cytoplasm – Medium only.

Q61. The cell organelles that convert sunlight into chemical energy are:

A) Ribosomes
B) Mitochondria
C) Chloroplasts
D) Golgi bodies

✅ Correct Answer: C) Chloroplasts

Explanation:

• A, B, D – Not for photosynthesis.
• C) ✔ Chloroplasts contain chlorophyll for photosynthesis.

Q62. Which scientist gave the name “cell” after observing cork?

A) Virchow
B) Hooke
C) Leeuwenhoek
D) Brown

✅ Correct Answer: B) Hooke

Explanation:

• B) ✔ Robert Hooke in 1665 saw cork cells under microscope.
• A, C, D – Other contributions.

Q63. Which of these organelles is called the “digestive bag”?

A) Lysosome
B) Vacuole
C) Ribosome
D) Golgi apparatus

✅ Correct Answer: A) Lysosome

Explanation:

• A) ✔ Lysosomes contain enzymes to digest waste/old organelles.
• B, C, D – Other jobs.

Q64. Which organelle modifies, packages, and secretes proteins?

A) Ribosome
B) Golgi apparatus
C) Lysosome
D) Endoplasmic reticulum

✅ Correct Answer: B) Golgi apparatus

Explanation:

• A) Ribosome – Synthesis only.
• B) ✔ Golgi processes and secretes proteins.
• C, D – Different roles.

Q65. Which cell organelle is called the “control room of the cell”?

A) Cytoplasm
B) Nucleus
C) Ribosome
D) Mitochondria

✅ Correct Answer: B) Nucleus

Explanation:

• A, C, D – Support functions.
• B) ✔ Nucleus regulates all cell activities.

Q66. Which cells in our body lack a nucleus?

A) White blood cells
B) Red blood cells
C) Muscle cells
D) Nerve cells

✅ Correct Answer: B) Red blood cells

Explanation:

• A, C, D – Contain nuclei.
• B) ✔ Mature RBCs lose nuclei to carry more oxygen.

Q67. Which plastid gives red, yellow, or orange colour to fruits and flowers?

A) Leucoplast
B) Chromoplast
C) Chloroplast
D) Mitochondria

✅ Correct Answer: B) Chromoplast

Explanation:

• A) Leucoplast – Colourless, storage.
• B) ✔ Chromoplast pigments give bright colours.
• C) Chloroplast – Green pigment.
• D) Mitochondria – Energy only.

Q68. Which structure in the nucleus contains hereditary information?

A) Chromosomes
B) Nucleolus
C) Nuclear pores
D) Nucleoplasm

✅ Correct Answer: A) Chromosomes

Explanation:

• A) ✔ Chromosomes have DNA and genes.
• B, C, D – Other nuclear components.

Q69. Which organelle helps in intracellular transport of proteins and lipids?

A) Ribosome
B) Endoplasmic reticulum
C) Lysosome
D) Golgi apparatus

✅ Correct Answer: B) Endoplasmic reticulum

Explanation:

• A) Ribosome – Makes proteins.
• B) ✔ ER transports proteins (rough ER) and lipids (smooth ER).
• C, D – Other functions.

Q70. Which cell organelle is called the “cell’s recycling unit”?

A) Lysosome
B) Mitochondria
C) Golgi apparatus
D) Ribosome

✅ Correct Answer: A) Lysosome

Explanation:

• A) ✔ Lysosomes digest waste material, recycle components.
• B, C, D – Not involved in recycling.

Q71. Which organelle gives the green colour to algae and plants?

A) Chromoplast
B) Chloroplast
C) Leucoplast
D) Ribosome

✅ Correct Answer: B) Chloroplast

Explanation:

• A, C, D – Not responsible for green pigment.
• B) ✔ Chlorophyll in chloroplasts gives green colour.

Q72. What is the fluid part of the cell excluding the nucleus called?

A) Cytoplasm
B) Protoplasm
C) Nucleoplasm
D) Chromatin

✅ Correct Answer: A) Cytoplasm

Explanation:

• A) ✔ Cytoplasm = cytosol + organelles (except nucleus).
• B) Protoplasm – Cytoplasm + nucleus.
• C, D – Inside nucleus.

Q73. Which part of the cell is called the “selectively permeable membrane”?

A) Cell wall
B) Cell membrane
C) Nuclear membrane
D) Vacuole

✅ Correct Answer: B) Cell membrane

Explanation:

• A) Cell wall – Fully permeable.
• B) ✔ Cell membrane allows only certain substances.
• C) Nuclear membrane – For nucleus.
• D) Vacuole – Storage.

Q74. The longest animal cell is found in:

A) Whale
B) Human nerve
C) Frog egg
D) Horse muscle

✅ Correct Answer: B) Human nerve

Explanation:

• A, C, D – Other cells.
• B) ✔ Nerve cells can extend up to 1 m in humans.

Q75. What is the main function of chromosomes?

A) Energy production
B) Heredity transmission
C) Food storage
D) Protein synthesis

✅ Correct Answer: B) Heredity transmission

Explanation:

• A, C, D – Other processes.
• B) ✔ Chromosomes carry DNA, transmit hereditary traits.

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