Skin: layers, sweat, goosebumps, freckles and sunburn

Tests: 3 of 11 right · Exam: 0 of 4 right · Kind: plain · Understood: 7 of 15 · Run: 2026-10-18, commit f3c23ea72

Lesson 353 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 · wrong ✗

«it's cloudy, don't need sun cream today» What is right?

1. You only burn when it feels hot — ← Mova's choice · no support
2. Sun cream works only on sunny days — no support
3. Clouds block all sunburn — no support
4. Ultraviolet light gets through clouds, so you can still burn — ✓ the right answer · 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 2 · wrong ✗

«sweat's just your body leaking, it's useless» What is the truth?

1. Sweat is only there to make you smell — ← Mova's choice · no support
2. Sweat makes you hotter — no support
3. Sweat cools you as it dries off the skin — ✓ the right answer · no support
4. Sweat cleans out all the dirt from the blood — 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 3 · right ✓

On a hot sticky humid day you sweat a lot but still feel hot. Why?

1. You stop sweating when it is humid — no support
2. Humid air has no oxygen in it, so the body cannot cool itself — no support
3. Sweat dries slowly in damp air, so it cools you less — ← Mova's choice · ✓ the right answer · score 4
4. Your sweat glands switch off — no support

Why: It took the question to ask why something happens (its cause). It chose option 3 with score 4, the only option with support. Its support: lesson 353, line 10: «Skin has two to four million sweat glands; sweat cools you as it dries, because drying takes heat from the skin, and on a humid day it dries slowly and cools l…», reached through the option's own match among the sentences about the question's things. What matched: the same action «cool» (+2); the same doer «sweat» (+1); its «because» matches the remembered cause (+1). · the question and its options parsed, with trees and pragmatics

Test 4 · right ✓

A cat sees a big dog and its fur stands up so it looks twice as big. What in your own skin works the same way?

1. Sweat, when the skin goes wet — no support
2. Freckles, when skin goes darker — no support
3. Goosebumps, when tiny muscles lift your hairs — ← Mova's choice · ✓ the right answer · score -1
4. Blushing, when the skin goes red — no support

Why: It took the question to ask what it is done to. It chose option 3 with score -1, the only option with support. Its support: lesson 317, line 12: «A North American porcupine has about 30,000 quills, stiff hairs with tiny barbs that work their way into skin; porcupines cannot shoot their quills.», reached through the same lesson line as the sentence the question matched. What matched: it fills the role the question asks for (+2); the same thing acted on «30,000 quills» (+1). Against it: a different doer (counts against) (-4). · the question and its options parsed, with trees and pragmatics

Test 5 · wrong ✗

In a Tom and Jerry cartoon Tom gets such a fright that every hair on him shoots up stiff as pins. What is true about that?

1. It happens to cats only in cartoons and films — ← Mova's choice · no support
2. Real cats can never raise their fur — no support
3. Fur only stands up in cold weather — no support
4. Fur really does stand up on a scared cat, but not that stiff or all at once — ✓ the right answer · 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 6 · wrong ✗

«my mate says brown skin and white skin have totally different cells inside» What is right?

1. Yes, lighter skin has no melanin at all — score 2
2. No, skin colour comes from the blood — no support
3. No, everyone has about the same colour cells; they just make different amounts of melanin — ✓ the right answer · score 2
4. Yes, darker skin has extra skin layers — ← Mova's choice · score 4

Why: It took the question to ask which statement is true. It chose option 4 with score 4, against 2 for the next best. Its support: lesson 353, line 7: «Skin has three main layers: the outer epidermis, the dermis with blood vessels and nerves, and a fat layer underneath; the outer layer has no blood vessels, so…», reached through the option's own match among the sentences about the question's things. What matched: the same light verb (be, have, do, get, go) (+2); the same doer «skin» (+1); the same thing acted on «three main layers» (+1). The right option, 3, scored 2. · the question and its options parsed, with trees and pragmatics

Test 7 · wrong ✗

Count them: the skin has three main layers. A doctor looks at skin from four children. How many layers in all?

1. 7 — ← Mova's choice · no support
2. 4 — no support
3. 3 — no support
4. 12 — ✓ the right answer · 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 · wrong ✗

Why do the soles of your feet need thicker skin than your eyelids?

1. They press on the ground with your whole weight every step — ✓ the right answer · no support
2. Feet need to keep the sweat in — no support
3. They are further from the brain, so they need extra skin to feel things — ← Mova's choice · score 4
4. Eyelids are made of a different organ — no support

Why: It took the question to ask why something happens (its cause). It chose option 3 with score 4, the only option with support. Its support: lesson 70, line 16: «Skin judges hot and cold by change: after warm water, lukewarm water feels cool, and after cold water, the same lukewarm water feels warm.», reached through the option's own match among the sentences about the question's things. What matched: the same action «feel» (+2); the same doer «skin» (+1); one says «not», the other does not (counts against) (+1). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 9 · wrong ✗

In a snowy ski resort a girl gets sunburnt on a cold day. How?

1. The very cold air burns the skin just like a hot flame does — ← Mova's choice · no support
2. Snow is full of salt — no support
3. She only got cold, not burnt — no support
4. Snow reflects the sun's ultraviolet light back onto her skin — ✓ the right answer · 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 · wrong ✗

«snake changes its skin all at once, so we must do it too, just slower innit» What is right?

1. We lose all our skin each night in bed — no support
2. We never lose any skin — no support
3. We change our whole skin in one go, once a year in summer — ← Mova's choice · score 4
4. We lose old skin bit by bit as tiny flakes all the time — ✓ the right answer · no support

Why: It took the question to ask which statement is true. It chose option 3 with score 4, the only option with support. Its support: lesson 353, line 9: «The outer layer of skin replaces itself about every four weeks, bit by bit, while a snake sheds its whole skin in one go.», reached through the option's own match among the sentences about the question's things. What matched: the same place «one go» (+4); the same thing acted on «whole skin» (+1). Against it: a different doer (counts against) (-1). The right option, 4, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 11 · right ✓

Why might people in a northern country take vitamin D in winter?

1. Winter food has no vitamins in it — score 3
2. The winter sun is too weak for skin to make enough — ← Mova's choice · ✓ the right answer · score 10
3. Thick coats stop the skin from making enough sweat to keep it healthy — no support
4. Cold kills vitamin D in the blood — no support

Why: It took the question to ask why something happens (its cause). It chose option 2 with score 10, against 3 for the next best. Its support: lesson 353, line 17: «Skin makes vitamin D in sunlight, which helps bones use calcium; in Britain the winter sun is too weak for this, so many people take vitamin D in autumn and wi…», reached through the cause of the sentence the question matched. What matched: the same property (+4); the same doer «winter sun» (+3); the same light verb (be, have, do, get, go) (+3). · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · wrong ✗

Identify the organ which, of all the organs of the human body, is the largest.

1. The lungs — ← Mova's choice · no support
2. The liver — no support
3. The brain — no support
4. The skin — ✓ the right answer · 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

Exam question 2 · formal language · wrong ✗

Which of the following statements most accurately characterises the mechanism whereby perspiration lowers body temperature?

1. Sweat diminishes the rate of circulation of the blood — ← Mova's choice · no support
2. Sweat is secreted at a temperature below that of the air — no support
3. Sweat obstructs the radiation of the sun — no support
4. Heat is withdrawn from the skin in the course of the evaporation of sweat — ✓ the right answer · 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

Exam question 3 · formal language · wrong ✗

Select the response consistent with the established facts concerning the colour of human skin.

1. It is determined by the quantity of perspiration secreted — no support
2. It is determined by the colour of the blood — ← Mova's choice · score 2
3. It is determined by the quantity of melanin produced, the number of pigment cells being broadly similar in all persons — ✓ the right answer · no support
4. It is determined by the number of layers of which the skin is composed — score 2

Why: It took the question to ask which statement is true. It chose option 2 with score 2, tied with another option at 2 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 53, line 3: «Some animals hide, but others want to be seen: the bright blue poison dart frog and the black and white skunk wear warning colours that say, loud and clear, do…», reached through the option's own match among the sentences about the question's things. What matched: the same doer «warning colours» (+1); the same thing acted on «warning colours» (+1). The right option, 3, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Exam question 4 · formal language · wrong ✗

Ascertain which of the following conditions affords no protection against sunburn.

1. A hat and shade — ← Mova's choice · no support
2. An overcast sky — ✓ the right answer · no support
3. The application of sun cream — no support
4. Garments covering the shoulders — 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

This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/biology/353-skin-layers-sweat-goosebumps-freckles-and-sunburn/