NEET 2025 MCQ with Answer Explanation : “The Living World”.

51. Which of the following structures are found in all living cells?
    a) Mitochondria
    b) Cell wall
    c) Ribosomes
    d) Chloroplasts

Answer: c) Ribosomes

Explanation:
Ribosomes are present in all cells, both prokaryotic and eukaryotic, as they are essential for protein synthesis. Mitochondria and chloroplasts are found only in eukaryotes, and cell walls are found in plants, fungi, and some prokaryotes.

52. Which scientist is credited with the introduction of the five-kingdom classification system?
    a) Linnaeus
    b) Darwin
    c) Whittaker
    d) Mendel

Answer: c) Whittaker

Explanation:
R.H. Whittaker proposed the five-kingdom classification system, dividing organisms into Monera, Protista, Fungi, Plantae, and Animalia.

53. Which of the following criteria is used in modern taxonomy for the classification of organisms?
    a) Structural similarities
    b) Molecular and genetic data
    c) Evolutionary relationships
    d) All of the above

Answer: d) All of the above

Explanation:
Modern taxonomy uses structural similarities, molecular and genetic data, and evolutionary relationships to classify organisms more accurately.

54. In the binomial nomenclature system, which part of the name is written in lowercase?
    a) Genus
    b) Species
    c) Family
    d) Order

Answer: b) Species

Explanation:
In binomial nomenclature, the genus name is capitalized, while the species name is written in lowercase, e.g., Homo sapiens.

55. Which of the following statements is true for Monera?
    a) All members have membrane-bound organelles
    b) Members are unicellular and prokaryotic
    c) All members are autotrophs
    d) All members are multicellular

Answer: b) Members are unicellular and prokaryotic

Explanation:
Organisms in the kingdom Monera are unicellular and prokaryotic, meaning they lack membrane-bound organelles and a true nucleus.

56. Organisms that live in extreme environmental conditions are called:
    a) Extremophiles
    b) Mesophiles
    c) Aerophiles
    d) Halophiles

Answer: a) Extremophiles

Explanation:
Extremophiles are organisms that thrive in extreme conditions, such as very high or low temperatures, acidic environments, or high salt concentrations.

57. Which of the following is an incorrect match between a group of organisms and their kingdom?
    a) Mosses – Plantae
    b) Bacteria – Monera
    c) Amoeba – Protista
    d) Yeast – Animalia

Answer: d) Yeast – Animalia

Explanation:
Yeast belongs to the kingdom Fungi, not Animalia. It is a unicellular fungus.

58. Which of the following is NOT a characteristic of living organisms?
    a) Metabolism
    b) Growth
    c) Adaptation to environment
    d) Permanent cessation of vital functions

Answer: d) Permanent cessation of vital functions

Explanation:
Permanent cessation of vital functions, such as metabolism, indicates death, which is not a characteristic of living organisms.

59. Which of the following pairs are correctly matched?
    a) Homo sapiens – Family
    b) Felis domestica – Genus
    c) Panthera leo – Order
    d) Musca domestica – Class

Answer: b) Felis domestica – Genus

Explanation:
Felis domestica (the domestic cat) belongs to the genus Felis. The other matches refer to incorrect taxonomic levels.

60. Which of the following taxonomic categories ranks higher than family?
    a) Genus
    b) Species
    c) Order
    d) Class

Answer: c) Order

Explanation:
In the taxonomic hierarchy, order ranks higher than family, and family ranks higher than genus and species.