MCQs / Biology / O Level Biology: Classification

O Level Biology: Classification MCQs — Biology

20 multiple-choice questions on O Level Biology: Classification from Biology, each with the correct answer and, where available, a teacher's explanation. Read through them to revise the chapter, then practise the same questions one by one to test yourself.

1. Which animal is a crustacean?

  1. Crab
  2. Spider
  3. Beetle
  4. Centipede

Answer: A) Crab

Explanation: Crabs have 2 pairs of antennae and 5+ pairs of legs. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

2. Use the key: 1a six legs → 2; 1b eight legs → spider. 2a wings → housefly; 2b no wings → ant. An animal with six legs and no wings is

  1. an ant
  2. a centipede
  3. a spider
  4. a housefly

Answer: A) an ant

Explanation: Six legs → step 2; no wings → ant. O Level Biology · Topic 2 Classification · 2.1 Concept and use of a classification system

Discuss this question

3. An arthropod has 3 pairs of legs, 3 body parts and 1 pair of antennae. It is

  1. an insect
  2. a crustacean
  3. a myriapod
  4. an arachnid

Answer: A) an insect

Explanation: Six legs and three body parts = insect. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

4. An animal has fur, external ears and mammary glands. It is a

  1. amphibian
  2. mammal
  3. reptile
  4. bird

Answer: B) mammal

Explanation: These are features of mammals. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

5. Which feature is best for a dichotomous key?

  1. Colour of a leaf in autumn
  2. Where it was found
  3. Number of legs
  4. Size of the animal

Answer: C) Number of legs

Explanation: Choose fixed, visible features. O Level Biology · Topic 2 Classification · 2.1 Concept and use of a classification system

Discuss this question

6. A species is best defined as a group of organisms that

  1. look exactly alike
  2. eat the same food
  3. can reproduce to produce fertile offspring
  4. live in the same habitat

Answer: C) can reproduce to produce fertile offspring

Explanation: This is the biological definition of a species. O Level Biology · Topic 2 Classification · 2.1 Concept and use of a classification system

Discuss this question

7. Which is the correct way to write the scientific name of humans?

  1. Homo sapiens
  2. HOMO sapiens
  3. homo Sapiens
  4. Homo Sapiens

Answer: A) Homo sapiens

Explanation: Genus capital, species small, italics. O Level Biology · Topic 2 Classification · 2.1 Concept and use of a classification system

Discuss this question

8. Which arthropod group has 4 pairs of legs and no antennae?

  1. Insects
  2. Crustaceans
  3. Myriapods
  4. Arachnids

Answer: D) Arachnids

Explanation: Spiders and scorpions are arachnids. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

9. Which group of vertebrates has dry scales and lays leathery eggs on land?

  1. Birds
  2. Reptiles
  3. Amphibians
  4. Fish

Answer: B) Reptiles

Explanation: Reptiles have dry scaly skin and soft-shelled eggs. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

10. Viruses can reproduce only

  1. in soil
  2. in water
  3. inside living cells
  4. by binary fission

Answer: C) inside living cells

Explanation: Viruses need a host cell's machinery. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

11. Which kingdom contains organisms with no nucleus?

  1. Plant
  2. Protoctist
  3. Fungus
  4. Prokaryote

Answer: D) Prokaryote

Explanation: Prokaryotes (bacteria) lack a nucleus. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

12. Which describes a virus?

  1. A cell with circular DNA and plasmids
  2. A cell with a nucleus and cell wall
  3. Genetic material surrounded by a protein coat
  4. A multicellular organism with hyphae

Answer: C) Genetic material surrounded by a protein coat

Explanation: Viruses are not cells: just nucleic acid in a protein coat. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

13. In the binomial name Panthera leo, "Panthera" is the

  1. kingdom
  2. family
  3. species
  4. genus

Answer: D) genus

Explanation: The first part of the binomial name is the genus. O Level Biology · Topic 2 Classification · 2.1 Concept and use of a classification system

Discuss this question

14. A plant has parallel leaf veins and flower parts in threes. It is a

  1. monocotyledon
  2. moss
  3. dicotyledon
  4. fern

Answer: A) monocotyledon

Explanation: Parallel veins and parts in threes are monocot features. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

15. Amphibians are different from reptiles because amphibians have

  1. fur
  2. moist skin with no scales
  3. dry scales
  4. feathers

Answer: B) moist skin with no scales

Explanation: Amphibians have moist, scaleless skin. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

16. Organisms are classified into groups mainly using

  1. features they share
  2. their size
  3. the number found
  4. their age

Answer: A) features they share

Explanation: Shared features show relationships. O Level Biology · Topic 2 Classification · 2.1 Concept and use of a classification system

Discuss this question

17. Ferns differ from flowering plants because ferns

  1. have no roots
  2. have no leaves
  3. reproduce by spores and have no flowers
  4. reproduce by seeds

Answer: C) reproduce by spores and have no flowers

Explanation: Ferns make spores, not seeds. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

18. Fungi feed by

  1. ingesting food into a gut
  2. absorbing light energy
  3. secreting enzymes onto food and absorbing the products
  4. photosynthesis

Answer: C) secreting enzymes onto food and absorbing the products

Explanation: This is saprotrophic nutrition. O Level Biology · Topic 2 Classification · 2.2 Features of organisms

Discuss this question

19. A dichotomous key works by

  1. listing organisms in order of size
  2. grouping organisms by where they live
  3. dividing organisms into two groups at each step using a feature
  4. naming organisms by colour only

Answer: C) dividing organisms into two groups at each step using a feature

Explanation: Dichotomous means dividing into two. O Level Biology · Topic 2 Classification · 2.1 Concept and use of a classification system

Discuss this question

20. A horse and a donkey produce an infertile mule. This shows that

  1. mules are a new species
  2. horses and donkeys are the same species
  3. only mules are mammals
  4. horses and donkeys are different species

Answer: D) horses and donkeys are different species

Explanation: Members of one species produce fertile offspring. O Level Biology · Topic 2 Classification · 2.1 Concept and use of a classification system

Discuss this question

Practise O Level Biology: Classification MCQs

More Biology chapters