O Level / IGCSE Biology chapter 2: Classification MCQs with answers
By Team Megalecture · Updated 4 Nov 2026
20 exam-style questions on Classification, each with the answer and a short explanation. Ten of them are below to try. The chapter test draws ten fresh questions each time and is marked the moment you finish, with your score by topic.
Concept and use of a classification system9 questions
Features of organisms11 questions
Ten Classification questions with answers
Try each one, then open the answer. These ten stay the same; the test draws new ones every time.
1. A horse and a donkey can mate to produce a mule, but mules are infertile. What does this show?
A
they belong to different genera, because they look different from each other
B
they are the same species, because they are able to mate with each other
C
they are different species, because the mule is infertile
D
the mule is a new species, because it is a mixture of both parents
Show answer
Answer: C. Members of one species can reproduce to produce fertile offspring. A mule is infertile, so a horse and a donkey are different species even though they can mate.
2. Which is the correct way to write the scientific name of humans?
A
Homo Sapien
B
sapiens Homo
C
H. Sapiens
D
Homo sapiens
Show answer
Answer: D. The genus comes first with a capital letter; the species name comes second, all in lower case, with the whole name in italics (or underlined when handwritten).
3. An arthropod has more than four pairs of jointed legs, two pairs of antennae and a hard outer shell. To which group does it belong?
A
crustaceans
B
insects
C
arachnids
D
myriapods
Show answer
Answer: A. Crustaceans such as crabs have more than four pairs of legs and two pairs of antennae. Myriapods have many body segments with legs on each and one pair of antennae.
4. Which feature is shown by all mammals but not by birds?
A
hair or fur on the skin, and mammary glands that produce milk for the young
B
a backbone with a vertebral column running down the back
C
lungs used for gas exchange, with a heart that has four chambers
D
a constant body temperature that is kept above that of the surroundings
Show answer
Answer: A. Only mammals have hair or fur and mammary glands. Birds are also vertebrates with a backbone, a constant body temperature and lungs.
5. Which features place an organism in the fungus kingdom?
A
single cells with no nucleus, whose DNA lies free in the cytoplasm
B
cells with cellulose walls and chloroplasts, making their own food by photosynthesis
C
cells with walls but no chloroplasts, feeding by absorbing digested food
D
many cells with no cell walls, feeding by taking in solid food and digesting it
Show answer
Answer: C. Fungi have cell walls but no chloroplasts, and they secrete enzymes onto their food and absorb the digested products. Plants make their own food, prokaryotes have no nucleus, and animals lack cell walls.
6. An arthropod has four pairs of legs, two body sections and no antennae. To which group does it belong?
A
insects
B
crustaceans
C
myriapods
D
arachnids
Show answer
Answer: D. Arachnids (such as spiders) have eight legs, two body parts and no antennae. Insects have six legs, three body parts and one pair of antennae.
7. How does a fern differ from a flowering plant?
A
a fern has no xylem, so water moves only by diffusion
B
a fern reproduces by spores and has no flowers or seeds
C
a fern has no chlorophyll, so it must absorb food from the soil
D
a fern has no roots, stems or leaves, only a flat green body
Show answer
Answer: B. Ferns reproduce using spores rather than seeds and have no flowers. They do have roots, stems, leaves, chlorophyll and xylem.
8. Two populations of birds live on separate islands and look slightly different. When they are brought together they mate and produce fertile chicks. What does this show?
A
they belong to different genera because they live on different islands
B
they belong to the same species
C
they belong to different species because they look different
D
they are hybrids of two species because they look different
Show answer
Answer: B. A species is a group of organisms that can reproduce to produce fertile offspring. Looking different or living apart does not make them separate species if they can interbreed successfully.
9. Cell X has a cell wall, ribosomes, a single circular chromosome and plasmids, but no nucleus and no mitochondria. In which kingdom is it placed?
A
plants
B
protoctists
C
fungi
D
prokaryotes
Show answer
Answer: D. A cell with no nucleus and with circular DNA and plasmids is a prokaryote (bacterium). Fungi, plants and protoctists all have a nucleus.
10. A dichotomous key is made to identify four different animals. What is the smallest total number of pairs of statements the whole key needs?
A
8
B
3
C
2
D
4
Show answer
Answer: B. Each pair of statements splits a group in two. Separating four animals needs three splits in total: one to divide them into two pairs, and one for each pair.
20, each with the answer and a short explanation, across 2 topics: Concept and use of a classification system, Features of organisms. Every chapter test draws ten of them, so you can take it many times.
Is the O Level / IGCSE Biology chapter 2 test free?
Yes. The test, the answers and the explanations are free and need no sign-up. Sign in only if you want your scores kept across devices.
How is the chapter test marked?
The moment you press Finish: your score, the right answer and an explanation for every question, and the ones you got wrong saved in My mistakes to retry.
