Biology · Unit 16

The Animal Kingdom

Classifying and comparing animals

Classification is often taught as a naming exercise, which makes it dull and slightly pointless. It is better understood as a claim about ancestry: putting two animals in the same group asserts they share a more recent common ancestor than either does with anything outside it.

The unit covers the taxonomic hierarchy, the vertebrate classes, the far larger and stranger world of invertebrates, and how body plans map onto ways of making a living.

This unit breaks down into 20 short steps and 120 questions, starting at difficulty 1 and building to 3. Below you can see exactly what it covers, how the path is structured, and worked examples with explanations.

Steps: 20
Questions: 120
Difficulty: 1-3

What this unit covers

Classification and Taxonomy
Vertebrates
Invertebrates
Animal Adaptations
Animal Behaviour

Where this fits

Works well before Evolution and Ecology, which explains why the groupings look the way they do.

Where people slip

Groups defined by a shared way of life rather than shared ancestry keep collapsing on inspection. Bats are not birds, whales are not fish, and both facts are about descent rather than about shape.

How the unit is structured

The Animal Kingdom runs as 20 short steps that unlock in order. 15 are practice rounds and 5 are challenge rounds that pull together everything before them. Questions start at difficulty 1 and climb to 3 as you progress.

Step 1 · easierStep 20 · harder

Challenge rounds

Example questions

30 real questions from this unit, with the answer and the reason behind it, grouped by what they practise. There are 120 in the unit altogether.

Animal Adaptations

Fill the blankLevel 1
1. An animal that eats both plants and other animals is called an ____.
- omnivorecorrect
- herbivore
- carnivore
- predator
Omnivores, such as bears and humans, eat both plants and animals.
Multiple choiceLevel 1
2. What is camouflage?
- Colours or patterns that help an animal blend into its surroundingscorrect
- Travelling a long way each year
- A deep sleep through the winter
- Eating only plants
Camouflage is colouring or patterns that help an animal blend into its surroundings.
Sort into groupsLevel 1
3. Sort each animal by what it eats: herbivore, carnivore or omnivore.
Answer: Cow = Herbivore; Rabbit = Herbivore; Lion = Carnivore; Wolf = Carnivore; Bear = Omnivore; Human = Omnivore
Herbivores eat only plants, carnivores eat only other animals, and omnivores eat both.
Fact or fibLevel 2
4. Ectotherms such as lizards often control their temperature by basking in the sun or moving into the shade.
Answer: True
Because ectotherms make little heat internally, they use behaviour - basking, seeking shade, burrowing - to warm up or cool down.
Match the pairsLevel 2
5. Match each extreme habitat to an animal adaptation that suits it.
Answer: Polar seas = Thick insulating blubber; Hot sandy desert = Water made from digesting dry seeds; Deep sea = A glowing bioluminescent lure; High mountains = Extra red blood cells for thin air
Each biome favours different adaptations: blubber for polar cold, water made from dry seeds for deserts, a glowing lure for the dark deep sea, and extra red blood cells for thin mountain air.
Picture questionLevel 2
6. 🐫 This desert animal has a hump as an adaptation. What does the hump mainly store?
- Fat, which it can use for energy
- Water as a pool of liquid
- Air for breathing underwater
- Sand to keep it cool
A camel's hump stores fat, which it can break down for energy when food and water are scarce.

Animal Behaviour

Build the sentenceLevel 2
7. A honeybee's waggle dance tells its hivemates two key things about a food source. Build the phrase.
Answer: the direction and distance to food
The angle and length of the waggle run signal the direction and distance to food, so other bees can fly straight to it.
Fact or fibLevel 2
8. All animal behaviour is learned after birth.
Answer: False
This is false; many behaviours are instincts that animals are born already knowing how to do.
Fill the blankLevel 2
9. Birds building the correct nest without ever being taught is an example of ____.
- instinctcorrect
- learning
- migration
- camouflage
Nest-building is an inborn, instinctive behaviour that birds do not need to learn.
Multiple choiceLevel 2
10. What is an instinct?
- A behaviour an animal is born knowing how to docorrect
- A skill taught by parents over many years
- A behaviour copied only from humans
- A type of body organ
An instinct is an inborn behaviour an animal can do without being taught, such as a spider spinning a web.
Tap the pairsLevel 2
11. Match each way of communicating to the animal that famously uses it.
Answer: Waggle dance = Honeybee; Scent trail = Ant; Complex song = Robin; Loud chorus of calls = Frog
Bees dance, ants lay scent trails, robins sing, and frogs call in loud choruses to communicate with others of their kind.
Sort into groupsLevel 3
12. Sort each behaviour into innate or learned.
Answer: A baby's grasping reflex = Innate; A spider spinning its web = Innate; Riding a bicycle = Learned; A dog sitting on command = Learned
Reflexes and web-spinning are inherited and need no practice, while cycling and obeying commands must be learned through experience.

Classification and Taxonomy

Fill the blankLevel 1
13. The smallest and most specific group in the classification system is the ____.
- speciescorrect
- kingdom
- phylum
- genus
Species is the smallest, most specific rank, and members of a species are very closely related.
Build the sentenceLevel 2
14. Build the sentence that describes what defines a species.
Answer: Members of one species can breed together
Members of the same species can breed together to produce fertile offspring.
Fact or fibLevel 2
15. Two species whose DNA base sequences are very similar are generally more closely related than two species with very different DNA.
Answer: True
Closely related species have had less time to build up genetic differences, so their DNA sequences stay more alike.
Multiple choiceLevel 2
16. What is the two-part naming system used to give every species a scientific name?
- Binomial nomenclaturecorrect
- The food chain
- Metamorphosis
- Natural selection
Binomial nomenclature gives each species a two-part Latin name made of its genus and species.
Odd one outLevel 2
17. Three of these are domains of life. Which one is NOT a domain?
- Bacteria
- Archaea
- Eukarya
- Protistacorrect
Bacteria, Archaea and Eukarya are the three domains; Protista is a kingdom within the Eukarya, not a domain.
Match the pairsLevel 3
18. Match each taxonomic rank to the correct group for human beings (Homo sapiens).
Answer: Kingdom = Animalia; Phylum = Chordata; Class = Mammalia; Genus = Homo
Humans are classified as Kingdom Animalia, Phylum Chordata, Class Mammalia and Genus Homo.

Invertebrates

Guess the numberLevel 1
19. How many legs does an insect, such as an ant or a beetle, have?
Answer: 6 legs
All adult insects have six legs, arranged as three pairs on the thorax.
Multiple choiceLevel 1
20. What do all invertebrates have in common?
- They have no backbonecorrect
- They all have wings
- They all live in water
- They all have six legs
Invertebrates are animals without a backbone, and they make up the large majority of animal species.
Fact or fibLevel 2
21. In a termite colony, the workers and soldiers are usually sterile and leave all the breeding to the king and queen.
Answer: True
True. Termite workers and soldiers normally cannot reproduce; only the royal pair breeds, which is a hallmark of a eusocial colony.
Fill the blankLevel 2
22. Crabs, lobsters and shrimp belong to a group of invertebrates called ____.
- crustaceanscorrect
- molluscs
- insects
- arachnids
Crustaceans such as crabs and lobsters have a hard exoskeleton and mostly live in water.
Build the sentenceLevel 3
23. Build the sentence explaining how an arthropod is able to grow.
Answer: arthropods must shed their exoskeleton to grow
Because their rigid exoskeleton cannot stretch, arthropods must periodically moult (shed) it to grow larger.
Choose all that applyLevel 3
24. Which of these are defining features of a truly eusocial insect colony, such as a honeybee hive? Select all that apply.
- Cooperative care of the youngcorrect
- Overlapping adult generations living togethercorrect
- A reproductive division of labour into castescorrect
- Every individual breeds equally
Eusociality means cooperative care of young, overlapping adult generations living together, and a reproductive division of labour into castes; it does NOT mean every individual breeds.

Vertebrates

Fill the blankLevel 1
25. Fish take in oxygen from water using their ____.
- gillscorrect
- lungs
- skin
- fins
Fish breathe using gills, which absorb dissolved oxygen from the water.
Multiple choiceLevel 1
26. What feature do all vertebrates share?
- A backbone (spine)correct
- Six legs
- An outer shell
- Feathers
Vertebrates are animals with a backbone, or spinal column, made of small bones called vertebrae.
Odd one outLevel 1
27. Which of these is NOT one of the five main groups of vertebrates?
- Insectscorrect
- Fish
- Amphibians
- Reptiles
Insects are invertebrates; the five vertebrate groups are fish, amphibians, reptiles, birds and mammals.
Choose all that applyLevel 2
28. Which two vertebrate groups are warm-blooded (able to control their own body temperature)? Select all that apply.
- Birdscorrect
- Mammalscorrect
- Fish
- Reptiles
Only birds and mammals are warm-blooded (endothermic); fish, amphibians and reptiles are cold-blooded.
Match the pairsLevel 2
29. Match each vertebrate group to one of its key features.
Answer: Mammals = Fur or hair; Birds = Feathers; Fish = Gills; Reptiles = Dry scales
Mammals have fur or hair, birds have feathers, fish have gills, and reptiles have dry scales.
Picture questionLevel 2
30. 🦇 This mammal flies at night and hunts insects in complete darkness by making sounds and listening for the echoes that bounce back. What is this ability called?
- Echolocationcorrect
- Electroreception
- Magnetoreception
- Bioluminescence
Bats (and toothed whales) use echolocation, emitting high-pitched sounds and reading the returning echoes to build a picture of their surroundings.

Where these questions come from. Each unit starts as a plan of the concepts it should cover and the difficulty it should span. Questions are written against that plan with AI assistance, then checked by a validator that rejects anything without a single defensible answer, an explanation, or plausible wrong options. How we write questions sets out the whole process, and corrections are fixed in the bank and reach the site and the app the same day.

How you practise

This unit mixes 17 different question formats, so you are recalling and applying rather than recognising the same layout every time.

Build the sentence
Choose all that apply
Fact or fib
Fill the blank
Guess the number
Listen and choose
Match the pairs
Multiple choice
Odd one out
Picture question
Put in order
Sequence recall
Sort into groups
Spell it
Tap the pairs
True or false
Type the answer

Practise The Animal Kingdom

120 questions across 20 steps. Start with step one and crawl at your own pace.

Play this unit

More units in Biology

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