---
title: Skin: fingerprints, scabs, scars, bruises and blisters — how Mova does on the tests · Biology
description: Lesson 354 of the biology course of Mova's primary school: 8 of 12 tests right, exam 1 of 4, every question with the options, the student's choice, the right answer and why it chose.
---

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# Skin: fingerprints, scabs, scars, bruises and blisters

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**Tests:** 8 of 12 right · **Exam:** 1 of 4 right · **Kind:** ★ · **Understood:** 8 of 16 · **Run:** 2026-10-18, commit `f3c23ea72`

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Lesson 354 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](https://md.mova.elamur.ai/free/en/corpora/school/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/).

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Every question of this lesson and each of its options parsed by Mova, with trees and pragmatics: [the lesson's questions in the corpora](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/).

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### Test 1 · ★ · wrong ✗ {#t1}

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«my twin's fingerprints are the same as mine, we can unlock each other's phones» What is right?

- **1.** Even identical twins have different fingerprints — **✓ the right answer** · no support
- **2.** Only the thumbs match in twins — no support
- **3.** Twins share fingerprints until they are ten — **← Mova's choice** · score 0
- **4.** Yes, twins share all their fingerprints, every single line — score 0

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**Why:** It took the question to ask which statement is true. It chose option 3 with score 0, tied with another option at 0 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 277, line 9: «You get half your DNA from your mother and half from your father; which parts you get is a mix, so brothers and sisters differ, but identical twins share the s…», reached through the option's own match among the sentences about the question's things. What matched: the same action «share» (+1); the same doer «identical twins» (+1). Against it: a different thing acted on (counts against) (-2). The right option, 1, found no support in what it remembers. · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t1/)

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### Test 2 · ★ · right ✓ {#t2}

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Count them: a boy finds 6 loops, 3 whorls and some arches on his ten fingers. How many arches?

- **1.** 1 — **← Mova's choice** · **✓ the right answer** · no support
- **2.** 0 — no support
- **3.** 2 — no support
- **4.** 3 — no support

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**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](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t2/)

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### Test 3 · ★ · wrong ✗ {#t3}

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«leave my scab alone, I'm picking it, it's mine» What is the best advice?

- **1.** Pick it, because it lets the air in and the skin heals faster that way — no support
- **2.** Put salt on it to dry it — no support
- **3.** Leave it, because picking can let germs in and slow healing — **✓ the right answer** · no support
- **4.** Pick it, scabs are full of germs — **← Mova's choice** · score 3

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**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 64, line 8: «A cut heals because skin cells around it divide and make new cells that crawl across the wound, while a scab protects it from germs.», reached through the option's own match among the sentences about the question's things. What matched: the same circumstance (+2); the same doer «scab» (+1). The right option, 3, found no support in what it remembers. · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t3/)

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### Test 4 · ★ · wrong ✗ {#t4}

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A bruise on Monday is red-purple. What colour is it most likely to be on Friday or Saturday?

- **1.** Bright red — **← Mova's choice** · no support
- **2.** Black — no support
- **3.** White — no support
- **4.** Green or yellow — **✓ the right answer** · no support

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**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](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t4/)

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### Test 5 · ★ · right ✓ {#t5}

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In a Tom and Jerry cartoon Tom is hit on the head and a huge bump shoots up in a second like a balloon, then vanishes. What really happens?

- **1.** Bumps disappear in seconds — no support
- **2.** A knock never causes swelling — no support
- **3.** Bumps can grow even taller than the head and then pop — no support
- **4.** A bump swells more slowly and can take days to go down — **← Mova's choice** · **✓ the right answer** · score 6

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**Why:** It took the question to ask which statement is true. It chose option 4 with score 6, the only option with support. Its support: lesson 194, line 13: «Always ask the owner before stroking a dog, let it sniff your hand, and stroke its side or chest rather than reaching over its head, because a hand coming down…», reached through the same lesson line as the sentence the question matched. What matched: the same action «come down» (+4); the same property (+1); a different doer (counts against) (+1). · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t5/)

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### Test 6 · ★ · right ✓ {#t6}

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«new shoes gave me a blister, I'm popping it with a pin» What is the best advice?

- **1.** Pop it with any pin, it does not matter — no support
- **2.** Rub it until it goes away — no support
- **3.** Pop it and peel off the loose skin so it dries faster — no support
- **4.** Do not pop it; let it heal under its own skin — **← Mova's choice** · **✓ the right answer** · score 4

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**Why:** It took the question to ask which statement is true. It chose option 4 with score 4, the only option with support. Its support: lesson 354, line 13: «A blister is a bubble of fluid between skin layers that forms from rubbing and cushions the damaged skin; it is best not popped, so it heals under its own skin.», reached through a sentence linked to the one the question matched. What matched: the same action «heal» (+3); the same place «own skin» (+2). Against it: a different doer (counts against) (-1). · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t6/)

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### Test 7 · ★ · right ✓ {#t7}

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Why does a scar feel different from the skin around it?

- **1.** It is tough fibres with no hair or sweat glands — **← Mova's choice** · **✓ the right answer** · no support
- **2.** It is a scab that never fell off — no support
- **3.** It is made of a thin plate of bone growing in the skin — no support
- **4.** It is dead skin with no blood at all — no support

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**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](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t7/)

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### Test 8 · ★ · right ✓ {#t8}

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«bit my cheek at lunch, it'll take a month to heal» What is right?

- **1.** Mouth wounds usually heal fast, in days — **← Mova's choice** · **✓ the right answer** · no support
- **2.** It heals slower than skin — no support
- **3.** It needs a plaster to heal — no support
- **4.** It will never heal at all — no support

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**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](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t8/)

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### Test 9 · ★ · right ✓ {#t9}

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Why are fingerprints useful to the police?

- **1.** They are unique and stay the same all your life — **← Mova's choice** · **✓ the right answer** · score 6
- **2.** They show what you ate — no support
- **3.** They change a little every year, so they show your age — no support
- **4.** Everyone in a family shares them — no support

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**Why:** It took the question to ask why something happens (its cause). It chose option 1 with score 6, the only option with support. Its support: lesson 354, line 5: «Fingerprints are unique; even identical twins have different ones, and they stay the same all your life, only bigger, which is why the police use them.», reached through the same lesson line as the sentence the question matched. What matched: the same light verb (be, have, do, get, go) (+3); the same property (+2); the same doer «fingerprints» (+1). · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t9/)

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### Test 10 · ★ · right ✓ {#t10}

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What would be harder for someone born without fingerprints?

- **1.** Tasting sweets — no support
- **2.** Hearing music — no support
- **3.** Gripping and feeling fine textures — **← Mova's choice** · **✓ the right answer** · score 5
- **4.** Seeing in the dark — no support

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**Why:** It took the question to ask which statement is true. It chose option 3 with score 5, the only option with support. Its support: lesson 354, line 9: «The ridges help you grip and help you feel textures, because stroking a surface makes tiny vibrations that nerves pick up; a very few people are born with no f…», reached through the same lesson line as the sentence the question matched. What matched: the same action «feel» (+4); the same thing acted on «textures» (+1). · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t10/)

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### Test 11 · ★ · right ✓ {#t11}

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A guitarist practises every day for months. What happens to her fingertips?

- **1.** They get thinner and softer each year — no support
- **2.** They grow thick protective calluses — **← Mova's choice** · **✓ the right answer** · score 3
- **3.** They lose their fingerprints for ever — no support
- **4.** They grow extra fingernails on their palms — score 0

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**Why:** It took the question to ask which statement is true. It chose option 2 with score 3, against 0 for the next best. Its support: lesson 354, line 4: «Skin even fights back against rubbing: a blister cushions a sore spot, and a guitarist's fingertips grow thick hard calluses.», reached through the option's own match among the sentences about the question's things. What matched: the same action «grow» (+1); the same doer «fingertips» (+1); the same thing acted on «thick hard calluses» (+1). · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t11/)

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### Test 12 · ★ · wrong ✗ {#t12}

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«why's my scab itchy, is it infected» What is the most likely reason?

- **1.** The scab is turning into a bruise — **← Mova's choice** · no support
- **2.** The scab is growing hair — no support
- **3.** Itching is often normal while new skin heals — **✓ the right answer** · no support
- **4.** Itching always means a bad infection that needs a doctor — no support

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**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](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/t12/)

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### Exam question 1 · formal language · wrong ✗ {#e1}

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Select the response consistent with the established facts concerning the fingerprints of identical twins.

- **1.** The fingerprints of such twins are identical in every respect — **← Mova's choice** · no support
- **2.** The fingerprints of such twins differ one from the other — **✓ the right answer** · no support
- **3.** Such twins possess no fingerprints — no support
- **4.** The fingerprints of such twins coincide upon the thumbs alone — no support

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**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](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/e1/)

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### Exam question 2 · formal language · right ✓ {#e2}

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Identify the principal function of a scab.

- **1.** The sealing of a wound whilst new skin forms beneath it — **← Mova's choice** · **✓ the right answer** · no support
- **2.** The permanent replacement of damaged skin — no support
- **3.** The importation of germs into the wound — no support
- **4.** The darkening of the skin about the wound — no support

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**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](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/e2/)

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### Exam question 3 · formal language · wrong ✗ {#e3}

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Which of the following sequences most accurately characterises the change in colour of a healing bruise?

- **1.** Red-purple, then blue, then green, then yellow — **✓ the right answer** · score 3
- **2.** Blue throughout, until it vanishes — no support
- **3.** Yellow, then green, then blue, then red — **← Mova's choice** · score 3
- **4.** Red, then black, then white — no support

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**Why:** It took the question to ask who or what does it. It chose option 3 with score 3, tied with another option at 3 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 92, line 16: «Live lobsters are usually greenish brown and turn red only when cooked, because heat breaks down a protein that hides the red colour; a rare blue lobster, by a…», reached through the option's own match among the sentences about the question's things. What matched: the same thing acted on «gene change» (+2); the same property (+1). The right option, 1, scored 3. · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/e3/)

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### Exam question 4 · formal language · wrong ✗ {#e4}

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State the recommended treatment of a blister occasioned by friction.

- **1.** It is to be treated with salt — **← Mova's choice** · no support
- **2.** It is to be rubbed until it disperses — no support
- **3.** It is to be popped forthwith with a pin — no support
- **4.** It is to be left unpopped, that it may heal beneath its own skin — **✓ the right answer** · no support

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**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](https://md.mova.elamur.ai/free/en/corpora/questions/biology/354-skin-fingerprints-scabs-scars-bruises-and-blisters/e4/)

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- ← previous: [353. Skin: layers, sweat, goosebumps, freckles and su…](https://md.mova.elamur.ai/free/en/school-run/biology/353-skin-layers-sweat-goosebumps-freckles-and-sunburn/)
- next →: [355. Hair: growing, curly and straight, eyebrows, eye…](https://md.mova.elamur.ai/free/en/school-run/biology/355-hair-growing-curly-and-straight-eyebrows-eyelashes-and-going-grey/)
- ↑ back to [Biology](https://md.mova.elamur.ai/free/en/school-run/biology/)