Bread rising: yeast at work

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

Lesson 21 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 · right ✓

Ollie's dough is in the fridge and hardly rising. His sister says the yeast is dead. What's more likely?

1. The flour has turned to salt — no support
2. It's just working slowly in the cold — ← Mova's choice · ✓ the right answer · score 5
3. Dough never rises in a fridge — score 5
4. Yes, fridges kill all yeast at once — score 2

Why: It took the question to ask which statement is true. It chose option 2 with score 5, tied with another option at 5 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 21, line 6: «Warmth makes yeast work faster, so dough is left somewhere warm; in a cold fridge it rises very slowly, which bakers use to make it tastier.», reached through the same lesson line as the sentence the question matched. What matched: the same action «work» (+3); the same doer «yeast» (+2). · the question and its options parsed, with trees and pragmatics

Test 2 · right ✓

"used water straight from the kettle for my yeast and nothing happened lol". Why?

1. The yeast was asleep, wait a week — no support
2. The yeast needed salt, not sugar — score 3
3. Kettle water has no oxygen — score 4
4. Water that's too hot kills yeast — ← Mova's choice · ✓ the right answer · score 7

Why: It took the question to ask why something happens (its cause). It chose option 4 with score 7, against 4 for the next best. Its support: lesson 21, line 11: «Yeast in warm sugary water wakes up, eats the sugar and foams; water that is too hot kills yeast.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «water» (+2); the same thing acted on «water» (+2); the same property (+2); the same light verb (be, have, do, get, go) (+1). · the question and its options parsed, with trees and pragmatics

Test 3 · wrong ✗

If you made bread dough but forgot to knead it at all, what would the bread be like?

1. Bigger and fluffier than ever — ← Mova's choice · no support
2. Exactly the same — no support
3. Flatter and more crumbly — ✓ the right answer · no support
4. Bright brown inside — 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 4 · wrong ✗

A cartoon shows a baker blowing into dough with a straw to make the holes. What really makes them?

1. Air from the oven fan — ← Mova's choice · no support
2. The baker's breath — no support
3. Gas from the yeast — ✓ the right answer · no support
4. Drops of 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

Test 5 · right ✓

Gran: "stale bread? pop it in the oven". Why does that work?

1. Warming softens it for a while — ← Mova's choice · ✓ the right answer · score 4
2. The oven adds fresh yeast — no support
3. The oven puts sugar back — no support
4. Heat turns the bread back into dough — no support

Why: It took the question to ask why something happens (its cause). It chose option 1 with score 4, the only option with support. Its support: lesson 21, line 13: «Bread goes stale as its starch slowly lines up and squeezes out water; warming it in the oven softens it for a while.», reached through a sentence linked to the one the question matched. What matched: the same action «soften» (+2); the same doer «warming» (+2); the same property (+1). Against it: a different thing acted on (counts against) (-1). · the question and its options parsed, with trees and pragmatics

Test 6 · right ✓

Leo says penicillin proves all mould is good to eat. What's true?

1. All mould is a medicine, so any mouldy bread is healthy — no support
2. Penicillin is made from yeast, not mould — score 3
3. Mould is never useful for anything — no support
4. One mould gave a medicine, but bread mould can be harmful — ← 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 3 for the next best. Its support: lesson 21, line 17: «Mould is a fungus related to yeast that grows from spores on damp bread; penicillin, a life-saving medicine, was first found from a mould, but mould on bread c…», reached through the remembered sentence the question matched. What matched: the same doer «mould» (+3); the same property (+2); the same light verb (be, have, do, get, go) (+2). · the question and its options parsed, with trees and pragmatics

Test 7 · wrong ✗

Which of these rises without any yeast?

1. A loaf of sourdough — ← Mova's choice · no support
2. A white sandwich loaf — no support
3. A sponge cake with whisked eggs — ✓ the right answer · no support
4. A bread roll — 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

Test 8 · right ✓

"how's the soufflé gone flat already, it looked amazing 2 mins ago??"

1. The air inside cooled and shrank — ← Mova's choice · ✓ the right answer · score 5
2. The yeast died in the cold — no support
3. Someone poked it with a fork — no support
4. The eggs went off in the oven — no support

Why: It took the question to ask which statement is true. It chose option 1 with score 5, the only option with support. Its support: lesson 21, line 16: «A soufflé sinks soon after leaving the oven because the air inside cools and shrinks.», reached through the same lesson line as the sentence the question matched. What matched: the same action «shrink» (+3); the same doer «air» (+2). · the question and its options parsed, with trees and pragmatics

Test 9 · right ✓

You put yeast in warm sugary water and it foams and smells bready. What has happened?

1. The yeast has turned into flour — score 3
2. The sugar has started boiling in the warm water — score 3
3. The water has gone off — score 2
4. The yeast woke up and is eating the sugar — ← Mova's choice · ✓ the right answer · score 6

Why: It took the question to ask which statement is true. It chose option 4 with score 6, against 3 for the next best. Its support: lesson 21, line 11: «Yeast in warm sugary water wakes up, eats the sugar and foams; water that is too hot kills yeast.», reached through a sentence linked to the one the question matched. What matched: the same action «eat» (+2); the same doer «yeast» (+2); the same thing acted on «sugar» (+2). · the question and its options parsed, with trees and pragmatics

Test 10 · right ✓

Why does the middle of a loaf stay soft when the crust gets crunchy?

1. Gluten stops all heat getting in — no support
2. The middle is made of cake — no support
3. The oven heat stops at the crust — no support
4. Its water keeps it below 100 °C — ← Mova's choice · ✓ the right answer · score 6

Why: It took the question to ask why something happens (its cause). It chose option 4 with score 6, the only option with support. Its support: lesson 21, line 3: «In the hot oven the outside browns into a crust, as sugars and proteins react with heat, while the inside stays soft because its water keeps it below 100 °C.», reached through the cause of the sentence the question matched. What matched: the same action «keep» (+5); the same doer «water» (+4). Against it: a different thing acted on (counts against) (-3). · the question and its options parsed, with trees and pragmatics

Test 11 · wrong ✗

"pitta's got no yeast so how's it got a pocket??"

1. Bakers blow it up like a balloon — ← Mova's choice · score 6
2. It's baked folded in half — no support
3. Steam from water inside puffs it up — ✓ the right answer · no support
4. It's cut open by a machine — no support

Why: It took the question to ask which statement is true. It chose option 1 with score 6, the only option with support. Its support: lesson 21, line 6: «Warmth makes yeast work faster, so dough is left somewhere warm; in a cold fridge it rises very slowly, which bakers use to make it tastier.», reached through the remembered sentence the question matched. What matched: the same thing acted on «yeast» (+5); the same doer «bakers» (+3). Against it: a different action (counts against) (-2). The right option, 3, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · wrong ✗

Identify the organism principally responsible for the rising of bread dough.

1. A virus present in flour — ← Mova's choice · no support
2. A species of bacterium found in salt — no support
3. A mould introduced by the oven — no support
4. Yeast, a microscopic fungus — ✓ 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 · right ✓

It is given that dough is kneaded thoroughly prior to rising. Ascertain the principal effect of such kneading.

1. The starch is converted entirely into sugar — no support
2. The yeast is destroyed by friction — no support
3. All the gas is expelled permanently and the yeast is rendered inactive — no support
4. Gluten proteins are aligned into elastic strands which retain gas — ← 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 21, line 7: «Kneading lines up gluten proteins into long stretchy strands that trap the gas like balloons.», reached through the option's own match among the sentences about the question's things. What matched: the same thing acted on «gluten proteins» (+2); the same place «long stretchy strands» (+2); the same action «line up» (+1). · the question and its options parsed, with trees and pragmatics

Exam question 3 · formal language · wrong ✗

Which of the following statements most accurately characterises the staling of bread?

1. Yeast consumes the remaining bread — ← Mova's choice · no support
2. Air introduces additional water into the loaf — no support
3. Mould converts the bread into stone — no support
4. Starch gradually realigns and expels water — ✓ 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 4 · formal language · right ✓

Select the response consistent with the established facts concerning the rising of a cake prepared without yeast.

1. The cake rises through the action of mould spores — score 7
2. Baking powder or whisked eggs supply gas that expands in the heat — ← Mova's choice · ✓ the right answer · score 9
3. The cake cannot rise in the absence of yeast — score 1
4. The cake rises because sugar becomes lighter than air — score 7

Why: It took the question to ask which statement is true. It chose option 2 with score 9, against 7 for the next best. Its support: lesson 21, line 15: «Cakes rise without yeast, using baking powder or whisked eggs to trap gas that expands in the oven heat.», reached through the same lesson line as the sentence the question matched. What matched: the same action «expand» (+3); the same doer «gas» (+2); the same thing acted on «gas» (+2); the same place «oven heat» (+2). · the question and its options parsed, with trees and pragmatics

This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/chemistry/21-bread-rising-yeast-at-work/