Dinosaurs & Prehistoric Life · Unit 15

Dinosaur Biology

Bone histology, breathing, temperature, senses and movement

This unit asks what dinosaurs were like as living animals - how they grew, breathed, moved and sensed the world - using evidence that has only become readable recently.

It covers bone histology and growth rates, air sacs and breathing, the warm-blooded debate, brains and senses, and biomechanical estimates of speed.

This unit breaks down into 18 short steps and 105 questions, starting at difficulty 3 and building to 4. Below you can see exactly what it covers, how the path is structured, and worked examples with explanations.

Steps: 18
Questions: 105
Difficulty: 3-4

What this unit covers

Bone Histology and Growth
Biomechanics and Speed
Warm or Cold Blooded?
Air Sacs and Breathing
Brains and Senses

Where this fits

The advanced core of the track. Needs Dinosaur Family Groups.

Where people slip

Warm-blooded and cold-blooded is a false binary here. The evidence points to metabolic strategies in between, and the honest answer varies by group.

How the unit is structured

Dinosaur Biology runs as 18 short steps that unlock in order. 13 are practice rounds and 5 are challenge rounds that pull together everything before them. Questions start at difficulty 3 and climb to 4 as you progress.

Step 1 · easierStep 18 · 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 105 in the unit altogether.

Air Sacs and Breathing

Choose all that applyLevel 3
1. Which features are shared by birds and many dinosaurs? Pick all that apply.
- Air sacscorrect
- Pneumatic vertebraecorrect
- Hollow limb bonescorrect
- A diaphragm like a mammal
Air sacs, pneumatic bones and hollow limb bones all appear in both.
Multiple choiceLevel 3
2. What are air sacs in the bird and dinosaur body?
- Chambers that move air through the lungscorrect
- Fat stores for winter
- Balance organs in the ear
- Muscles in the tail
They are thin-walled chambers connected to the lungs that pump air through in one direction.
True or falseLevel 3
3. Hollow spaces in dinosaur vertebrae show where air sacs invaded the skeleton.
Answer: True
True. Pneumatic bones are strong evidence for the system.
Type the answerLevel 3
4. What word describes bones hollowed out by air sacs?
Answer: pneumatic
Pneumatic bones are light but strong.
Multiple choiceLevel 3
5. Why is one-way airflow through the lung efficient?
- Fresh air flows across the lung on both breathscorrect
- It requires no muscles
- It stores oxygen for days
- It works only underwater
Fresh air passes over the exchange surfaces on both inhalation and exhalation.
Choose all that applyLevel 4
6. Which advantages might air sacs bring? Pick all that apply.
- Efficient oxygen uptakecorrect
- A lighter skeletoncorrect
- Better heat managementcorrect
- Improved eyesight
Efficient oxygen uptake, lighter skeletons and heat management are all proposed.

Biomechanics and Speed

Build the sentenceLevel 3
7. Build a sentence about studying dinosaur biology.
Answer: Bones record how fast animals grew
Bones record how fast an animal grew.
Match the pairsLevel 3
8. Match each method to what it tells us.
Answer: Bone histology = Growth and age; CT endocasts = Brain and senses; Trackways = Movement and speed; Pneumatic bones = Breathing system
Different techniques answer different biological questions.
Multiple choiceLevel 3
9. What does biomechanics study in palaeontology?
- How extinct animals moved and fed, using physics
- How fossils are named
- How rocks form
- How museums are designed
It applies physics and engineering to work out how extinct animals moved and fed.
Put in orderLevel 3
10. Put the steps of a biomechanical study in order.
Answer: Digitise the skeleton -> Reconstruct muscles -> Run simulations -> Compare with trackway data
Digitise the skeleton, add muscles, run simulations, then compare with trackway evidence.
Choose all that applyLevel 4
11. Which evidence informs locomotion studies? Pick all that apply.
- Trackwayscorrect
- Joint surfaces and range of motioncorrect
- Computer simulationcorrect
- Fossilised footwear
Trackways, joint anatomy, muscle scars and modelling all contribute.
Fact or fibLevel 4
12. A good study reports the range of plausible results rather than one confident figure.
Answer: True
True. Honest uncertainty is a strength, not a weakness.

Bone Histology and Growth

Choose all that applyLevel 3
13. What can bone microstructure reveal? Pick all that apply.
- Approximate age at deathcorrect
- Growth ratecorrect
- Whether the animal was fully growncorrect
- Skin colour
Age, growth rate, maturity and sometimes reproductive state can all be read.
Fill the blankLevel 3
14. Comparing many individuals lets researchers build a growth ____ for a species.
- curvecorrect
- colour
- map
- cage
A growth curve plots size against age.
Multiple choiceLevel 3
15. What is bone histology?
- The study of bone microstructure in thin slicescorrect
- The study of bone weight
- The study of bone colour
- The naming of bones
It is the study of bone microstructure, usually by cutting and examining thin slices.
True or falseLevel 3
16. Cutting a thin section destroys part of the specimen, so permission is needed.
Answer: True
True. Sampling is a serious decision for rare fossils.
Type the answerLevel 3
17. What are the growth marks in bone that often form yearly called?
Answer: lines of arrested growth
Lines of arrested growth record pauses in growth.
Choose all that applyLevel 4
18. Which bones are commonly sampled for histology? Pick all that apply.
- Femurcorrect
- Tibiacorrect
- Ribscorrect
- Teeth enamel only
Long bones and ribs are preferred because they record growth clearly.

Brains and Senses

Choose all that applyLevel 3
19. What can CT scans of skulls reveal? Pick all that apply.
- Brain cavity shapecorrect
- Inner ear structurecorrect
- Air passages in the skullcorrect
- The animal's last thought
Brain shape, inner ear structure, air passages and nerve paths can all be modelled.
Multiple choiceLevel 3
20. What did large olfactory regions in the Tyrannosaurus brain suggest?
- An excellent sense of smellcorrect
- Poor eyesight
- Very good hearing only
- An inability to move
They indicate a very keen sense of smell.
True or falseLevel 3
21. The inner ear canals can indicate how an animal habitually held its head.
Answer: True
True. The semicircular canals are usually held in a consistent orientation.
Type the answerLevel 3
22. Which scanning technique reveals the inside of a fossil skull without breaking it?
Answer: CT scanning
CT scanning creates a digital model of internal spaces.
Multiple choiceLevel 3
23. What is an endocast?
- A model of the inside of the braincasecorrect
- A cast of the outside of the skull
- A model of the ribcage
- A copy of a footprint
It is a model of the space inside the braincase, showing the shape of the brain and nerves.
Choose all that applyLevel 4
24. Which senses can be studied from fossils? Pick all that apply.
- Smellcorrect
- Hearingcorrect
- Balance and head posturecorrect
- Taste preferences
Smell, hearing, vision and balance all leave anatomical traces.

Warm or Cold Blooded?

Choose all that applyLevel 3
25. Which lines of evidence bear on dinosaur metabolism? Pick all that apply.
- Growth rates from histologycorrect
- Isotopic temperature estimatescorrect
- Dinosaurs living in polar regionscorrect
- The colour of the fossil rock
Growth rates, bone structure, isotopes and polar occurrences all contribute.
Fact or fibLevel 3
26. Dinosaur fossils have been found within the ancient polar circles.
Answer: True
True. Alaska, Antarctica and Australia have all yielded polar dinosaurs.
Multiple choiceLevel 3
27. What does endothermic mean?
- Generating body heat internallycorrect
- Relying on the sun for warmth
- Living underwater
- Being cold all the time
An endotherm generates its own body heat internally, like birds and mammals.
True or falseLevel 3
28. The evidence suggests many dinosaurs were neither classic reptiles nor exactly like mammals in their metabolism.
Answer: True
True. An intermediate condition is often proposed.
Type the answerLevel 3
29. What term describes a metabolism between fully warm-blooded and fully cold-blooded?
Answer: mesothermy
Mesothermy has been proposed for many dinosaurs.
Choose all that applyLevel 4
30. Which strategies could polar dinosaurs have used? Pick all that apply.
- Seasonal migrationcorrect
- Feather or fuzz insulationcorrect
- Flexible diets in wintercorrect
- Hibernating for centuries
Migration, insulation, tolerating low light and dietary flexibility are all possible.

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 10 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
Match the pairs
Multiple choice
Put in order
Sort into groups
True or false
Type the answer

Practise Dinosaur Biology

105 questions across 18 steps. Start with step one and crawl at your own pace.

Play this unit

Read about Dinosaur Biology

Explainers from our blog on what this unit covers. Each one ends with real questions from the bank.

Were Dinosaurs Warm-Blooded? What Bones, Feathers and Growth Rings SuggestFor a century dinosaurs were pictured as sluggish reptiles. Bone structure, growth rates, feathers and chemistry now point to warm blood in most of them.September 14, 2026 · 4 min read

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