Leaves, fruit and colour in nature

Tests: 5 of 11 right · Exam: 2 of 4 right · Kind: ★ · Understood: 7 of 15 · Run: 2026-10-18, commit f3c23ea72

Lesson 28 of the chemistry 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 ✗

Lily: "leaves go yellow in autumn cos they get painted by the cold". What's true?

1. She's right, cold paints the leaves — ← Mova's choice · no support
2. The yellow was there, hidden by green — ✓ the right answer · no support
3. Leaves turn yellow from the rain — no support
4. Leaves soak up yellow light in autumn — 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 · ★ · right ✓

If a zoo fed its flamingos only plain food with no pink pigments, what would happen?

1. They would turn green like leaves — score 2
2. They would turn bright orange — score 2
3. They would slowly turn white — ← Mova's choice · ✓ the right answer · score 5
4. They would stay pink for ever and ever — score 1

Why: It took the question to ask which statement is true. It chose option 3 with score 5, against 2 for the next best. Its support: lesson 28, line 10: «Flamingos get their pink from pigments in the shrimps and algae they eat; fed without those pigments, they slowly turn white.», reached through the same lesson line as the sentence the question matched. What matched: the same action «turn» (+4); the same property (+1). · the question and its options parsed, with trees and pragmatics

Test 3 · ★ · right ✓

"my veins are blue so my blood's blue inside, obvs". What's true?

1. Blood is always red; it only looks blue through skin — ← Mova's choice · ✓ the right answer · score 4
2. Yes, blood is blue until it meets air — no support
3. No, blood is actually green inside — no support
4. Yes, blue blood is in the veins only — no support

Why: It took the question to ask which statement is true. It chose option 1 with score 4, the only option with support. Its support: lesson 28, line 15: «Veins look blue through the skin because of the way skin lets through and scatters light.», reached through the remembered sentence the question matched. What matched: the same action «look» (+4); the same property (+2). Against it: a different doer (counts against) (-2). · the question and its options parsed, with trees and pragmatics

Test 4 · ★ · right ✓

Grandad says carrots let RAF pilots see in the dark. What's the real story?

1. Carrots really did give the pilots night vision — score 5
2. Carrots were the pilots' only food — score 7
3. That story is usually said to have hidden radar — ← Mova's choice · ✓ the right answer · score 12
4. Pilots ate carrots to stay awake — no support

Why: It took the question to ask what it is done to. It chose option 3 with score 12, against 7 for the next best. Its support: lesson 28, line 9: «Carrots help your eyes only if you lack vitamin A; the story that carrots gave pilots night vision is usually said to have been spread in the Second World War…», reached through the remembered sentence the question matched. What matched: the same action «say» (+4); it fills the role the question asks for (+4); the same thing acted on «story» (+2); the same property (+2). · the question and its options parsed, with trees and pragmatics

Test 5 · ★ · right ✓

Jack wants to see a rainbow and looks straight at the setting Sun after a shower. Where should he look?

1. Away from the Sun, with it behind him — ← Mova's choice · ✓ the right answer · no support
2. Up at the very top of the sky — no support
3. Straight down at the puddles — no support
4. Straight into the Sun — 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 ✗

Your green tomatoes won't ripen. "stick 'em in a bag with a banana", says Nan. Why?

1. The banana keeps them in the dark — ← Mova's choice · score -1
2. The banana's yellow rubs onto them — no support
3. The banana's ethylene gas speeds ripening — ✓ the right answer · no support
4. The banana's sugar slowly soaks into the tomatoes — no support

Why: It took the question to ask why something happens (its cause). It chose option 1 with score -1, the only option with support. Its support: lesson 28, line 7: «As a tomato ripens its green fades and a red pigment called lycopene builds up; tomatoes ripen faster next to bananas because bananas give off a gas called eth…», reached through the cause of the sentence the question matched. What matched: the same doer «bananas» (+4). Against it: a different action (counts against) (-2); a different thing acted on (counts against) (-3). The right option, 3, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 7 · ★ · wrong ✗

A cartoon octopus takes an hour to change colour. What's more true?

1. Some can change in less than a second — ✓ the right answer · no support
2. They change only by eating coloured food — no support
3. They change only when they are fast asleep — no support
4. Octopuses cannot really change colour at all — ← Mova's choice · score 1

Why: It took the question to ask which statement is true. It chose option 4 with score 1, the only option with support. Its support: lesson 14, line 12: «Oxygen is a very reactive gas; a cut apple and a cut piece of some metals both change colour in air, in very different ways.», reached through the remembered sentence the question matched. What matched: the same thing acted on «colour» (+5); the same action «change» (+4). Against it: a different doer (counts against) (-2); one says «not», the other does not (counts against) (-6). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 8 · ★ · right ✓

Which colour comes from structure, not pigment?

1. The orange of a carrot — score 5
2. The rainbow shine on a peacock feather — ← Mova's choice · ✓ the right answer · score 12
3. The green of a leaf — score 5
4. The red of a tomato — score 12

Why: It took the question to ask who or what does it. It chose option 2 with score 12, tied with another option at 12 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 28, line 11: «The rainbow shine of some beetles, peacock feathers and butterfly wings comes from tiny layered structures that reflect light like a soap bubble, not from pigm…», reached through the remembered sentence the question matched. What matched: the same place «tiny layered structures» (+4); it fills the role the question asks for (+4); the same action «come» (+2); the same doer «rainbow shine» (+2). · the question and its options parsed, with trees and pragmatics

Test 9 · ★ · wrong ✗

If there were no air around the Earth, what colour would the daytime sky look?

1. Blue — ← Mova's choice · score 4
2. Red — no support
3. White — no support
4. Black — ✓ the right answer · no support

Why: It took the question to ask what it is done to. It chose option 1 with score 4, the only option with support. Its support: lesson 28, line 15: «Veins look blue through the skin because of the way skin lets through and scatters light.», reached through the remembered sentence the question matched. What matched: the same action «look» (+4); the same property (+2). Against it: a different doer (counts against) (-2). The right option, 4, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 10 · ★ · wrong ✗

"why's the sunset red, the sun's on fire more at night or what?"

1. The Moon makes the Sun look red — ← Mova's choice · no support
2. Its light goes through more air and loses blue — ✓ the right answer · no support
3. The sea reflects red light onto clouds — no support
4. Yes, the Sun burns hotter at night than in the day — 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 11 · ★ · wrong ✗

Which is true?

1. Chlorophyll makes leaves green so they look nice — ← Mova's choice · no support
2. Chlorophyll is made only in autumn — no support
3. Plants use the light chlorophyll soaks up to make food — ✓ the right answer · no support
4. Chlorophyll reflects red light — no support

Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · wrong ✗

Identify the principal reason for which the foliage of most plants appears green during summer.

1. The leaves reflect the colour of surrounding vegetation — ← Mova's choice · no support
2. Chlorophyll absorbs red and blue light and reflects green light — ✓ the right answer · no support
3. Summer sunlight consists predominantly of green light — no support
4. The leaves contain a reservoir of green water — 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 · right ✓

Which of the following statements most accurately characterises the pink coloration of flamingos?

1. It derives from pigments in their diet of shrimps and algae — ← Mova's choice · ✓ the right answer · no support
2. It is produced by blood visible through the feathers — no support
3. It is an inherited colour present from hatching — no support
4. It results from prolonged standing in pink water — no support

Why: Nothing it remembers matched the question, 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 that is consistent with the established facts concerning the colour of human blood.

1. It is blue whilst within the veins — ← Mova's choice · no support
2. It is colourless within the body — no support
3. It is invariably red, varying only in shade — ✓ the right answer · no support
4. It becomes red only upon contact with air — 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 4 · formal language · right ✓

It is given that an observer wishes to view a rainbow. Ascertain the position of the Sun required.

1. Behind the observer — ← Mova's choice · ✓ the right answer · no support
2. Directly before the observer — no support
3. Below the observer's horizon — no support
4. Directly overhead at noon — 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/chemistry/28-colour-in-nature/