Chapter 8: Cell – The Unit of Life – Case-Based / Source-Based Questions with Answers

CBSE Class 11 Biology Case-Based Questions: Cell – The Unit of Life (NCERT-Based)

Course and Examination Framework

Course: CBSE Class 11 Biology

Board: Central Board of Secondary Education

Unit III: Cell Structure and Function

Chapter 8: Cell – The Unit of Life

Question Type: Case-Based / Source-Based Questions

Syllabus Compliance: Strictly as per NCERT

Assessment Focus: Definitions, Comparisons, Concept Application

Exam Relevance: CBSE Class 11 Annual & School Examinations

Section A: Cell Theory and Basic Concepts (Cases 1–6)

Case 1

A biologist states that all organisms begin life as a single microscopic unit which later divides and differentiates.

Q1. Identify the concept being described.
Ans: Cell theory.

Q2. Name the scientist who added the concept of cell division from pre-existing cells.
Ans: Rudolf Virchow.

Case 2

An organism performs respiration, nutrition, and reproduction within a single microscopic unit.

Q3. What type of organism is this?
Ans: Unicellular organism.

Case 3

Two scientists independently studied plant and animal tissues and proposed a unifying theory.

Q4. Name the scientists.
Ans: Matthias Schleiden and Theodor Schwann.

Case 4

A student observes box-like empty structures while viewing cork under a microscope.

Q5. Identify the scientist associated with this observation.
Ans: Robert Hooke.

Case 5

A living organism lacks cellular organization but shows metabolic activities.

Q6. Why is it not considered a living cell?
Ans: Cellular organization is essential for life; viruses lack cellular structure.

Case 6

A cell divides repeatedly to form tissues and organs.

Q7. Which property of cell is illustrated?
Ans: Cell growth and differentiation.

Section B: Prokaryotic vs Eukaryotic Cells (Cases 7–12)

Case 7

A microscopic cell has circular DNA, no nucleus, and no membrane-bound organelles.

Q8. Identify the type of cell.
Ans: Prokaryotic cell.

Case 8

A cell contains linear chromosomes enclosed within a nuclear membrane.

Q9. Identify the cell type.
Ans: Eukaryotic cell.

Case 9

A cell shows 70S ribosomes and a nucleoid region.

Q10. Name the organism group it belongs to.
Ans: Bacteria (Prokaryotes).

Case 10

A student compares two cells—one has histone proteins and the other does not.

Q11. Which cell lacks histones?
Ans: Prokaryotic cell.

Case 11

An organism shows compartmentalization of cellular functions.

Q12. Which type of cell exhibits this feature?
Ans: Eukaryotic cell.

Case 12

A cell has mitochondria, Golgi apparatus, and endoplasmic reticulum.

Q13. Why are these organelles absent in prokaryotes?
Ans: Prokaryotes lack membrane-bound organelles.

Section C: Cell Membrane and Cell Wall (Cases 13–17)

Case 13

A membrane allows oxygen to pass freely but restricts large molecules.

Q14. Name this membrane property.
Ans: Selective permeability.

Case 14

A membrane structure shows phospholipid bilayer with embedded proteins.

Q15. Identify the model explaining this structure.
Ans: Fluid Mosaic Model.

Case 15

A plant cell placed in hypotonic solution does not burst.

Q16. Which structure prevents bursting?
Ans: Cell wall.

Case 16

A cell engulfs solid particles by forming membrane-bound vesicles.

Q17. Identify the process.
Ans: Phagocytosis.

Case 17

Ions move across the membrane against concentration gradient using ATP.

Q18. Name the transport mechanism.
Ans: Active transport.

Section D: Cell Organelles (Cases 18–25)

Case 18

A cell organelle synthesizes proteins and has ribosomes attached to its surface.

Q19. Identify the organelle.
Ans: Rough endoplasmic reticulum.

Case 19

An organelle modifies, packages, and transports proteins.

Q20. Name the organelle.
Ans: Golgi apparatus.

Case 20

A damaged cell releases enzymes that digest its own components.

Q21. Identify the organelle involved.
Ans: Lysosome.

Case 21

An organelle has its own DNA and ribosomes and produces ATP.

Q22. Name the organelle.
Ans: Mitochondrion.

Case 22

Photosynthesis occurs in an organelle containing grana and thylakoids.

Q23. Identify the organelle.
Ans: Chloroplast.

Case 23

A non-membranous structure synthesizes proteins in cytoplasm.

Q24. Name the structure.
Ans: Ribosome.

Case 24

A large central sac maintains turgidity in plant cells.

Q25. Identify the structure.
Ans: Vacuole.

Case 25

An animal cell lacks a specific organelle found in plant cells.

Q26. Name one such organelle.
Ans: Cell wall (or chloroplast).

Learning Outcomes (CBSE Focus)

Enhances application-based understanding
Strengthens cell structure–function correlation
Aligns with competency-based CBSE assessment
Ideal for case-based and source-based exam questions