Defences: skunks, porcupines, hedgehogs and armour

Tests: 8 of 11 right · Exam: 3 of 4 right · Kind: plain · Understood: 12 of 15 · Run: 2026-10-18, commit f3c23ea72

Lesson 248 of the biology course of Mova's primary school, as Mova's small model took its tests: it had read this lesson and the ones before it and learned from their exercises. Each test shows the options in the order the student saw them, its choice, the right answer, the score of every option and why it chose. The lesson itself, sentence by sentence with trees and pragmatics: the lesson in the corpora.

Every question of this lesson and each of its options parsed by Mova, with trees and pragmatics: the lesson's questions in the corpora.

Test 1 · right ✓

In a Tom and Jerry style cartoon, a porcupine shoots quills like arrows and Tom gets stuck full of them from far away. What is right?

1. Porcupines can fire their quills more than a hundred metres — no support
2. Porcupines shoot quills only at cats — score 7
3. Porcupines have no quills at all — score 4
4. Porcupines cannot shoot quills, they come out when touched — ← Mova's choice · ✓ the right answer · score 9

Why: It took the question to ask which statement is true. It chose option 4 with score 9, against 7 for the next best. Its support: lesson 248, line 7: «Porcupines cannot shoot their quills; the quills come out easily when touched, have tiny barbs that work into an attacker's skin, and grow back; a North Americ…», reached through the option's own match among the sentences about the question's things. What matched: the same action «come out» (+4); the same property (+3); the same doer «quills» (+2). · the question and its options parsed, with trees and pragmatics

Test 2 · right ✓

In a cartoon a skunk lifts its tail and everyone faints at once. What does a real skunk do first?

1. Warns by stamping, hissing and raising its tail — ← Mova's choice · ✓ the right answer · score 9
2. Hugs its enemy tightly until it gives up and goes — no support
3. Faints at once — no support
4. Bites with venom fangs — no support

Why: It took the question to ask what is done. It chose option 1 with score 9, the only option with support. Its support: lesson 248, line 6: «Skunks spray a very smelly oily liquid from glands under the tail at an attacker's face, but first warn by stamping, hissing and raising the tail, and spotted…», reached through the option's own match among the sentences about the question's things. What matched: the same thing acted on «tail» (+3); it fills the role the question asks for (+3); the same action «raise» (+2); a different doer (counts against) (+1). · the question and its options parsed, with trees and pragmatics

Test 3 · right ✓

In a cartoon a tortoise jumps out of its shell and runs off in its pants. What is true?

1. Tortoises swap their old shells for bigger ones every single spring — score 3
2. A tortoise can never leave its shell, it is part of its skeleton — ← Mova's choice · ✓ the right answer · score 4
3. Tortoises keep spare shells at home — score 3
4. Old tortoises leave their shells behind when it is time to die — score 3

Why: It took the question to ask which statement is true. It chose option 2 with score 4, against 3 for the next best. Its support: lesson 248, line 2: «A hedgehog rolls into a tight ball of spines, a pangolin curls up in scales so tough that a lion cannot bite through, and a tortoise pulls its head into a shel…», reached through the same lesson line as the sentence the question matched. What matched: the same thing acted on «part» (+3); the same circumstance (+1); the same light verb (be, have, do, get, go) (+1). Against it: a different doer (counts against) (-1). · the question and its options parsed, with trees and pragmatics

Test 4 · right ✓

«Sonic rolls into a ball and smashes stuff, real hedgehogs do that right» What is right?

1. Yes, they roll at their enemies at high speed, like spiky bowling balls — score 7
2. Yes, they smash rocks by rolling — score 6
3. No, hedgehogs cannot roll up — no support
4. They roll into a ball to protect themselves, not to attack — ← Mova's choice · ✓ the right answer · score 10

Why: It took the question to ask which statement is true. It chose option 4 with score 10, against 7 for the next best. Its support: lesson 248, line 2: «A hedgehog rolls into a tight ball of spines, a pangolin curls up in scales so tough that a lion cannot bite through, and a tortoise pulls its head into a shel…», reached through the option's own match among the sentences about the question's things. What matched: the same action «roll» (+4); the same place «tight ball» (+4); the same doer «hedgehog» (+2). · the question and its options parsed, with trees and pragmatics

Test 5 · wrong ✗

«dog got sprayed by a skunk, dump tomato juice on him» What is true?

1. Tomato juice makes the dog spray back — no support
2. Tomato juice does not really wash the smell off — ✓ the right answer · no support
3. Tomato juice removes all of the smell at once, after one bath — no support
4. Tomato juice makes it smell of roses — ← Mova's choice · score 3

Why: It took the question to ask which statement is true. It chose option 4 with score 3, the only option with support. Its support: lesson 248, line 6: «Skunks spray a very smelly oily liquid from glands under the tail at an attacker's face, but first warn by stamping, hissing and raising the tail, and spotted…», reached through the same lesson line as the sentence the question matched. What matched: the same thing acted on «skunk» (+3); the same doer «tomato juice» (+1). Against it: a different action (counts against) (-1). The right option, 2, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 6 · right ✓

«3 crabs on the beach, no wait 4. how many claws»

1. 8 — ← Mova's choice · ✓ the right answer · no support
2. 12 — no support
3. 6 — no support
4. 40 — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 7 · wrong ✗

«2 hedgehogs and 3 tortoises. legs?»

1. 10 — ← Mova's choice · no support
2. 15 — no support
3. 20 — ✓ the right answer · no support
4. 24 — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 8 · right ✓

What would happen if a horned lizard squirted blood at a hawk?

1. The hawk would be blinded for life by the blood in its eyes — score 5
2. The hawk would fall asleep straight away — score 3
3. The hawk would turn blue — score 3
4. Not much, the blood tastes nasty to dogs but not to birds — ← Mova's choice · ✓ the right answer · score 14

Why: It took the question to ask what happens next. It chose option 4 with score 14, against 5 for the next best. Its support: lesson 248, line 15: «The horned lizard squirts blood from its eyes, sometimes over a metre, at dogs and coyotes; the blood tastes nasty to dogs but not to birds, so it uses this on…», reached through what followed the sentence the question matched. What matched: the same action «taste» (+6); the same circumstance (+5); the same doer «blood» (+3). · the question and its options parsed, with trees and pragmatics

Test 9 · wrong ✗

«my mum reckons that pangolin is a pine cone with legs lol» What is it really?

1. A baby armadillo — ← Mova's choice · no support
2. A kind of lizard with feathers that lives in the trees of Africa — no support
3. A mammal with keratin scales that rolls up in danger — ✓ the right answer · no support
4. A walking plant with green leaves — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 10 · right ✓

«picked up a bug and now my fingers stink, gross» What was it probably?

1. A spider spinning a web between the leaves — score 1
2. A ladybird laying eggs — no support
3. A bee making honey in its hive — no support
4. A stink bug defending itself with smelly chemicals — ← Mova's choice · ✓ the right answer · score 4

Why: It took the question to ask what it is done to. It chose option 4 with score 4, against 1 for the next best. Its support: lesson 245, line 10: «Chimpanzees and other great apes bend branches into a fresh sleeping nest each night, off the cold ground and away from leopards, and a study found chimp nests…», reached through the remembered sentence the question matched. What matched: it fills the role the question asks for (+4); the same thing acted on «fewer bugs» (+2). Against it: a different doer (counts against) (-2). · the question and its options parsed, with trees and pragmatics

Test 11 · right ✓

A crab loses a claw in a fight. What can happen?

1. Many crabs grow it back over several moults — ← Mova's choice · ✓ the right answer · score 11
2. It turns into a different animal — score 6
3. It stays without a claw for ever — score 6
4. It grows two claws in its place at once — score 6

Why: It took the question to ask which statement is true. It chose option 1 with score 11, against 6 for the next best. Its support: lesson 248, line 16: «Crabs raise their claws to look bigger, male fiddler crabs wave one giant claw, and many crabs can grow back a lost claw over several moults.», reached through the option's own match among the sentences about the question's things. What matched: the same action «grow back» (+4); the same place «several moults» (+4); the same doer «many crabs» (+2); the same thing acted on «lost claw» (+1). · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · wrong ✗

Which of the following statements most accurately characterises the defensive conduct of the porcupine?

1. Its barbed quills detach readily upon contact but cannot be projected — ✓ the right answer · no support
2. It discharges its quills over considerable distances, much as an archer looses arrows — ← Mova's choice · score -2
3. It possesses venomous quills in the manner of a scorpion — no support
4. It relies exclusively upon flight from its pursuers — no support

Why: It took the question to ask who or what does it. It chose option 2 with score -2, the only option with support. Its support: lesson 154, line 1: «Cartoons love animal tricks: a bull goes mad at a red cape, a camel unscrews its hump and pours out water, a porcupine fires quills like arrows, and Tom the ca…», reached through the option's own match among the sentences about the question's things. What matched: the same thing acted on «quills» (+2). Against it: the same action «fire» (-2); a different doer (counts against) (-2). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Exam question 2 · formal language · right ✓

Identify the principal reason for which a tortoise is incapable of vacating its shell.

1. The shell is fastened by a lock of hardened mud — no support
2. The tortoise is too large to pass through the openings — score 6
3. The shell is cemented to the skin by saliva which sets as hard as stone — no support
4. The shell forms part of its skeleton, being joined to the backbone and ribs — ← Mova's choice · ✓ the right answer · score 7

Why: It took the question to ask which statement is true. It chose option 4 with score 7, against 6 for the next best. Its support: lesson 248, line 11: «A tortoise's shell is part of its skeleton, joined to its backbone and ribs, so it can never climb out; some tortoises live over 150 years, and Jonathan on Sai…», reached through the option's own match among the sentences about the question's things. What matched: the same action «join» (+4); the same doer «shell» (+2); the same circumstance (+1). · the question and its options parsed, with trees and pragmatics

Exam question 3 · formal language · right ✓

Select the response consistent with the established facts concerning the defence of the bombardier beetle.

1. It stings with a venomous appendage upon its head, injecting a paralysing fluid — no support
2. It feigns death for a period of several hours — no support
3. It emits a beam of light which dazzles its attackers — no support
4. Two chemicals are combined within a chamber and react to discharge a boiling spray — ← Mova's choice · ✓ the right answer · score 5

Why: It took the question to ask which statement is true. It chose option 4 with score 5, the only option with support. Its support: lesson 146, line 2: «Breathing fire would need a store of fuel and a spark, and the animal's own soft, wet mouth would burn; the bombardier beetle comes closest, firing a nearly bo…», reached through the option's own match among the sentences about the question's things. What matched: the same action «fire» (+4); the same thing acted on «boiling chemical spray» (+1). · the question and its options parsed, with trees and pragmatics

Exam question 4 · formal language · right ✓

Ascertain the conduct of the skunk prior to the discharge of its spray.

1. It discharges its spray without any prior warning whatsoever, even at the faintest sound — score 3
2. It summons other skunks by a loud call — no support
3. It retreats into a burrow and seals the entrance — no support
4. It issues warnings by stamping, hissing and the raising of its tail — ← Mova's choice · ✓ the right answer · score 5

Why: It took the question to ask which statement is true. It chose option 4 with score 5, against 3 for the next best. Its support: lesson 248, line 6: «Skunks spray a very smelly oily liquid from glands under the tail at an attacker's face, but first warn by stamping, hissing and raising the tail, and spotted…», reached through the option's own match among the sentences about the question's things. What matched: the same action «raise» (+4); the same thing acted on «tail» (+1). · the question and its options parsed, with trees and pragmatics

This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/biology/248-defences-skunks-porcupines-hedgehogs-and-armour/