Below is a well-structured, NCERT-aligned set of 50 MCQs with answers and detailed explanations for:

Course: CBSE Class 11 Biology – MCQs with Answers and Explanations
Unit I: Diversity in Living World
Topic: Living World (NCERT)

The questions are strictly based on NCERT content, framed in an exam-oriented, concept-clearing manner, suitable for CBSE Board standard.

MCQs on Living World – CBSE Class 11 Biology (NCERT)

Section A: Introduction to Living World (Concept of Life)

Q1. Which of the following is NOT a defining characteristic of living organisms?

A. Growth
B. Reproduction
C. Metabolism
D. Consciousness

Answer: B

Explanation:
Reproduction is not a defining property because some living organisms (e.g., mules, worker bees) do not reproduce. Metabolism and consciousness are universal features of living beings.

Q2. Increase in mass and number due to cell division is termed as:

A. Reproduction
B. Development
C. Growth
D. Metabolism

Answer: C

Explanation:
Growth refers to an irreversible increase in mass or number of cells due to cell division, which is a common feature of living organisms.

Q3. Which characteristic distinguishes living growth from non-living growth?

A. Increase in size
B. Increase in mass
C. Increase by cell division
D. Increase in volume

Answer: C

Explanation:
Living organisms grow by cell division, whereas non-living objects increase in size by external accumulation of matter.

Q4. Metabolism refers to:

A. Only photosynthesis
B. Only respiration
C. Sum total of chemical reactions in the body
D. Energy release reactions only

Answer: C

Explanation:
Metabolism includes all anabolic (building) and catabolic (breaking) reactions occurring within a living organism.

Q5. Which statement is correct regarding metabolism?

A. Occurs only in animals
B. Can occur in dead organisms
C. Occurs in all living organisms
D. Occurs only at cellular level

Answer: C

Explanation:
Metabolism is a defining feature of all living organisms and ceases after death.

Section B: Consciousness and Responsiveness

Q6. The ability of organisms to respond to stimuli is called:

A. Growth
B. Adaptation
C. Consciousness
D. Evolution

Answer: C

Explanation:
Consciousness refers to awareness of surroundings and the ability to respond to environmental stimuli, a unique property of living organisms.

Q7. Which of the following is considered the most important defining feature of life?

A. Reproduction
B. Growth
C. Consciousness
D. Locomotion

Answer: C

Explanation:
Consciousness includes responsiveness to stimuli and is present in all living organisms, making it the most defining feature.

Q8. Plants show consciousness through:

A. Locomotion
B. Photosynthesis
C. Growth towards stimuli
D. Reproduction

Answer: C

Explanation:
Plants respond to light, gravity, and water through directional growth, indicating consciousness.

Section C: Diversity in the Living World

Q9. The total number of plant and animal species described so far is approximately:

A. 1.2 million
B. 1.7 million
C. 7 million
D. 10 million

Answer: B

Explanation:
About 1.7–1.8 million species have been identified and described, as per NCERT data.

Q10. The estimated number of species on Earth ranges between:

A. 2–3 million
B. 5–10 million
C. 10–20 million
D. 20–50 million

Answer: B

Explanation:
Scientists estimate that the total number of species on Earth ranges from 5 to 10 million.

Q11. Which group has the maximum number of described species?

A. Fungi
B. Plants
C. Insects
D. Bacteria

Answer: C

Explanation:
Insects constitute the largest group of organisms, representing more than 70% of known animal species.

Section D: Nomenclature and Binomial System

Q12. Scientific naming of organisms is called:

A. Taxonomy
B. Classification
C. Nomenclature
D. Identification

Answer: C

Explanation:
Nomenclature refers to the process of assigning scientific names to organisms.

Q13. The system of binomial nomenclature was proposed by:

A. Darwin
B. Aristotle
C. Linnaeus
D. Whittaker

Answer: C

Explanation:
Carolus Linnaeus proposed the binomial nomenclature system, which gives each organism two names.

Q14. In Mangifera indica, the word Mangifera represents:

A. Species
B. Variety
C. Genus
D. Family

Answer: C

Explanation:
The first word of a scientific name denotes the genus, while the second indicates the species.

Q15. Which rule of binomial nomenclature is correct?

A. Names are written in English
B. Genus name starts with small letter
C. Species name starts with capital letter
D. Names are printed in italics

Answer: D

Explanation:
Scientific names are printed in italics (or underlined separately when handwritten).

Q16. The language used universally for scientific naming is:

A. English
B. Greek
C. Latin
D. Sanskrit

Answer: C

Explanation:
Latin is used because it is a dead language and does not change with time.

Section E: Taxonomic Categories and Hierarchy

Q17. Arrangement of organisms into groups based on similarities is called:

A. Nomenclature
B. Identification
C. Classification
D. Taxonomy

Answer: C

Explanation:
Classification involves grouping organisms based on shared characteristics.

Q18. The basic unit of classification is:

A. Genus
B. Species
C. Family
D. Order

Answer: B

Explanation:
Species is the smallest and most basic unit of classification.

Q19. Which taxonomic category includes organisms with maximum similarities?

A. Family
B. Genus
C. Species
D. Order

Answer: C

Explanation:
Members of the same species share maximum similarities.

Q20. Correct sequence of taxonomic hierarchy is:

A. Kingdom → Phylum → Class → Order → Family → Genus → Species
B. Kingdom → Class → Phylum → Order → Family → Species → Genus
C. Species → Genus → Family → Order → Class → Phylum → Kingdom
D. Genus → Species → Family → Order → Class → Kingdom → Phylum

Answer: A

Explanation:
This is the standard hierarchical order followed in biological classification.

Section F: Taxonomical Aids

Q21. Herbarium is a storehouse of:

A. Living plants
B. Preserved plant specimens
C. Preserved animals
D. Fossils

Answer: B

Explanation:
Herbaria store dried, pressed, and preserved plant specimens mounted on sheets.

Q22. Botanical gardens are useful because they:

A. Preserve animals
B. Preserve fossils
C. Maintain living plant collections
D. Maintain microorganisms

Answer: C

Explanation:
Botanical gardens maintain living plants for study, conservation, and research.

Q23. Museum specimens are preserved using:

A. Formalin
B. Glycerine
C. Alcohol
D. All of these

Answer: D

Explanation:
Different preservatives are used depending on the type of specimen.

Q24. Which taxonomical aid provides information in an alphabetical order?

A. Flora
B. Manuals
C. Monographs
D. Keys

Answer: B

Explanation:
Manuals provide identification information in a systematic and alphabetical manner.

Q25. Taxonomic keys are based on:

A. Similarities
B. Contrasting characters
C. Habitat
D. Genetic makeup

Answer: B

Explanation:
Keys use contrasting characteristics (couplets) to identify organisms.

Section G: Advanced Conceptual MCQs

Q26. Living organisms show cellular organization except:

A. Bacteria
B. Amoeba
C. Virus
D. Paramecium

Answer: C

Explanation:
Viruses are acellular and show characteristics of living beings only inside host cells.

Q27. Which of the following is a correct statement?

A. All growing organisms reproduce
B. All reproducing organisms grow
C. All living organisms reproduce
D. Growth defines living beings

Answer: B

Explanation:
Reproducing organisms must grow, but not all living organisms reproduce.

Q28. Which taxonomic aid provides complete information about a single taxon?

A. Manual
B. Flora
C. Monograph
D. Key

Answer: C

Explanation:
A monograph provides detailed information on a particular taxon.

Q29. Who is known as the Father of Taxonomy?

A. Aristotle
B. Darwin
C. Linnaeus
D. Whittaker

Answer: C

Explanation:
Carolus Linnaeus laid the foundation of modern taxonomy.

Q30. In scientific names, author’s name indicates:

A. Habitat
B. Discoverer
C. Place of origin
D. Classification

Answer: B

Explanation:
The author’s name represents the scientist who first described the species.

Section H: Case-Based / Assertion-Level MCQs

Q31. Assertion: Metabolism is a defining feature of living organisms.

Reason: All metabolic reactions can occur in test tubes.

A. Both true, reason correct
B. Both true, reason incorrect
C. Assertion true, reason false
D. Both false

Answer: C

Explanation:
Metabolism is defining, but metabolic reactions cannot occur outside living systems in totality.

Q32. Which taxonomic category comes just above genus?

A. Species
B. Family
C. Order
D. Class

Answer: B

Explanation:
Family includes one or more genera.

Q33. Correct example of binomial nomenclature is:

A. Homo Sapiens
B. Homo sapiens
C. homo Sapiens
D. Homo sapiens Linnaeus

Answer: B

Explanation:
Genus begins with a capital letter and species with a small letter.

Q34. Which taxonomic aid is most useful for field studies?

A. Museum
B. Herbarium
C. Botanical garden
D. Manual

Answer: D

Explanation:
Manuals help in quick identification during field studies.

Q35. The study of principles of classification is called:

A. Systematics
B. Taxonomy
C. Ecology
D. Morphology

Answer: A

Explanation:
Systematics includes classification, nomenclature, and evolutionary relationships.

Section I: Higher-Order Thinking MCQs

Q36. Species diversity is maximum in:

A. Temperate regions
B. Polar regions
C. Tropical regions
D. Desert regions

Answer: C

Explanation:
Tropical regions have stable climate and high productivity, supporting greater biodiversity.

Q37. Which statement supports the need for classification?

A. To increase species number
B. To study evolution
C. To simplify organism study
D. To name organisms

Answer: C

Explanation:
Classification helps organize vast biodiversity for easier study.

Q38. Which one is NOT a taxonomic aid?

A. Herbarium
B. Flora
C. Monograph
D. Ecosystem

Answer: D

Explanation:
Ecosystem is a functional unit, not a taxonomic aid.

Q39. Why Latin is preferred for scientific names?

A. Easy to learn
B. Universal acceptance
C. Ancient language
D. Does not change

Answer: D

Explanation:
Latin is a dead language, so names remain unchanged.

Q40. Which category has the least number of organisms?

A. Class
B. Family
C. Species
D. Order

Answer: C

Explanation:
Species is the smallest unit and contains the least number of organisms.

Section J: Final Revision MCQs (NCERT Rapid Check)

Q41. Identification in taxonomy refers to:

A. Naming of organism
B. Grouping of organisms
C. Correct placement of organism in taxonomic hierarchy
D. Study of evolutionary history

Answer: C

Explanation:
Identification involves determining whether an organism belongs to a known group and placing it correctly in the taxonomic hierarchy using available literature and taxonomic aids.

Q42. A book providing information about plant species of a particular area is called:

A. Manual
B. Flora
C. Monograph
D. Catalogue

Answer: B

Explanation:
Flora contains detailed descriptions of plant species found in a specific geographical region, including habitat and distribution.

Q43. Growth in plants differs from animals because plants:

A. Grow only up to maturity
B. Grow throughout life
C. Show cellular growth only
D. Do not grow by cell division

Answer: B

Explanation:
Plants show indeterminate growth due to the presence of meristematic tissues, whereas animals generally show determinate growth.

Q44. Viruses are considered non-living outside the host because they:

A. Cannot respire
B. Lack genetic material
C. Do not show metabolism
D. Lack cell wall

Answer: C

Explanation:
Viruses do not exhibit metabolism outside the host cell, which is a defining characteristic of living organisms.

Q45. A genus is a group of:

A. Closely related families
B. Closely related species
C. Similar orders
D. Identical organisms

Answer: B

Explanation:
A genus consists of one or more closely related species that share common characteristics.

Q46. Botanical gardens are important taxonomical aids because they:

A. Preserve dried plant specimens
B. Preserve fossils
C. Maintain living plant collections
D. Maintain animal specimens

Answer: C

Explanation:
Botanical gardens maintain living plants for study, reference, conservation, and research purposes.

Q47. Taxonomic keys are based on:

A. Similar characteristics
B. Evolutionary history
C. Dichotomous contrasting characters
D. Habitat of organisms

Answer: C

Explanation:
Taxonomic keys consist of paired contrasting characters (dichotomy) that help in identifying organisms step by step.

Q48. Taxonomy includes the study of:

A. Only classification
B. Only nomenclature
C. Identification, nomenclature, and classification
D. Ecology and evolution

Answer: C

Explanation:
Taxonomy deals with identification, naming (nomenclature), and classification of organisms.

Q49. Which of the following is a universal property of living organisms?

A. Reproduction
B. Growth
C. Metabolism
D. Locomotion

Answer: C

Explanation:
Metabolism is present in all living organisms and is considered a defining feature of life.

Q50. The binomial system of nomenclature consists of:

A. Common name and scientific name
B. Genus and family names
C. Species and family names
D. Genus name and species name

Answer: D

Explanation:
Binomial nomenclature assigns each organism a scientific name consisting of two parts: the genus name and the species name.