Chapter 2: Biological Classification – Case-Based / Source-Based Questions with Answers
CBSE Class 11 Biology Case-Based / Source-Based Questions – Chapter 2: Biological Classification (NCERT Based)
Course Details
Course: CBSE Class 11 Biology
Syllabus: NCERT
Unit: Unit I – Diversity in Living World
Chapter: Chapter 2 – Biological Classification
CBSE Board Examination: Central Board of Secondary Education – Class 11 (School & Annual Examinations)
CBSE Class 11 Biology Chapter 2 Biological Classification – Case-Based & Source-Based Questions (NCERT)
Section A: Five Kingdom Classification (Case 1–5)
Case 1
A biologist groups organisms based on cell structure, body organisation, and mode of nutrition.
Q1. Which classification system is being used?
Answer: The Five Kingdom Classification proposed by R.H. Whittaker is being used.
Q2. State one advantage of this classification system.
Answer: It reflects natural and evolutionary relationships among organisms.
Case 2
An organism lacks a true nucleus and membrane-bound organelles.
Q3. To which kingdom does it belong?
Answer: It belongs to Kingdom Monera.
Q4. Name one characteristic feature supporting this classification.
Answer: Presence of prokaryotic cell organisation.
Case 3
A unicellular organism has a true nucleus and lives in aquatic habitats.
Q5. Identify the kingdom of this organism.
Answer: The organism belongs to Kingdom Protista.
Q6. State one additional feature of this kingdom.
Answer: Protists show diverse modes of nutrition and locomotion.
Case 4
An organism shows absorptive heterotrophic nutrition and has chitin in its cell wall.
Q7. To which kingdom does it belong?
Answer: It belongs to Kingdom Fungi.
Case 5
A multicellular organism synthesises its own food using chlorophyll.
Q8. Identify the kingdom and mode of nutrition.
Answer: Kingdom Plantae; autotrophic nutrition by photosynthesis.
Section B: Kingdom Monera (Case 6–9)
Case 6
Bacteria found in soil convert atmospheric nitrogen into usable forms.
Q9. What is this process called?
Answer: Nitrogen fixation.
Q10. State the significance of this process.
Answer: It increases soil fertility and supports plant growth.
Case 7
A bacterium survives in extreme hot springs.
Q11. What type of bacteria is this?
Answer: It is an extremophile bacterium.
Case 8
An organism lacks a cell wall and shows pleomorphic shapes.
Q12. Identify the organism.
Answer: Mycoplasma.
Case 9
Photosynthetic prokaryotes form blooms in water bodies.
Q13. Name these organisms.
Answer: Cyanobacteria.
Section C: Protista and Fungi (Case 10–13)
Case 10
Microscopic organisms with siliceous cell walls form deposits called diatomaceous earth.
Q14. Identify the group of organisms.
Answer: Diatoms.
Case 11
A protozoan moves using pseudopodia and ingests food particles.
Q15. Name the organism type.
Answer: Amoeba, a protozoan.
Case 12
A fungus reproduces using spores and forms a mycelial network.
Q16. Name the vegetative structure involved.
Answer: Mycelium formed by hyphae.
Case 13
A fungus is used in the production of antibiotics.
Q17. Name the fungus and antibiotic.
Answer: Penicillium; penicillin.
Section D: Plantae and Animalia (Case 14–16)
Case 14
An organism has cellulose cell walls and stores food as starch.
Q18. Identify the kingdom.
Answer: Kingdom Plantae.
Case 15
An organism lacks cell walls and shows ingestive heterotrophic nutrition.
Q19. To which kingdom does it belong?
Answer: Kingdom Animalia.
Case 16
Animals show complex tissue and organ systems.
Q20. What does this indicate about their body organisation?
Answer: They have advanced multicellular organisation.
Section E: Viruses, Viroids & Lichens (Case 17–20)
Case 17
An infectious agent consists of nucleic acid and a protein coat.
Q21. Identify the agent.
Answer: Virus.
Case 18
An infectious RNA molecule without protein coat causes plant disease.
Q22. What is this agent called?
Answer: Viroid.
Case 19
A symbiotic association helps organisms survive in extreme habitats.
Q23. Name the association.
Answer: Lichen.
Case 20
An organism disappears from polluted areas.
Q24. What does this indicate?
Answer: The organism is sensitive to air pollution and acts as a pollution indicator.
Exam Relevance
✔ Fully NCERT-aligned
✔ Ideal for CBSE Class 11 case-based/source-based questions
✔ Focus on classification logic and application
✔ Suitable for internal assessments and annual examinations