Big snakes: pythons, boas and anacondas, and how big they really get

Tests: 8 of 11 right · Exam: 2 of 4 right · Kind: ★ · Understood: 10 of 15 · Run: 2026-10-18, commit f3c23ea72

Lesson 321 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 ✓

«mate there's a 15 metre anaconda that ate a whole canoe, saw the poster» What is the best reply?

1. True, but only in the Everglades — no support
2. No snake anywhere near that long has ever been measured; posters exaggerate — ← Mova's choice · ✓ the right answer · score 3
3. True, they eat canoes every summer — no support
4. It is real, and 15 metres is only a small one; the big ones are twice as long — score 3

Why: It took the question to ask which statement is true. It chose option 2 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 158, line 3: «A scientist checks a tale by measuring and testing: no anaconda over about seven metres has ever been well measured, and the candiru story rests on a few uncle…», reached through the option's own match among the sentences about the question's things. What matched: the same action «measure» (+3). · the question and its options parsed, with trees and pragmatics

Test 2 · ★ · wrong ✗

Count them: a museum has 3 python skeletons. How many legs and how many little leg spurs?

1. 6 legs and 6 spurs — ← Mova's choice · no support
2. No legs, but 6 spurs — ✓ the right answer · no support
3. No legs and no spurs — no support
4. 12 legs and no spurs — 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 · ★ · wrong ✗

Count them: a python has 300 backbones and almost every one has two ribs. About how many ribs is that?

1. Only about 150 — ← Mova's choice · no support
2. Only about 300 — no support
3. About 600 — ✓ the right answer · no support
4. Only about 33 — 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 · ★ · right ✓

Count them: 4 anacondas lie in a river. How many outer ears can you see?

1. 16, four each — no support
2. 8, two on each head — no support
3. None, snakes have no outer ears — ← Mova's choice · ✓ the right answer · score 5
4. 4, one each — no support

Why: It took the question to ask what it is done to. It chose option 3 with score 5, the only option with support. Its support: lesson 137, line 12: «Snakes have no outside ears but feel vibrations through their jaw bones; they have no eyelids, so they stare without blinking, but they cannot hypnotise anyone.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «snakes» (+2); the same light verb (be, have, do, get, go) (+2); it fills the role the question asks for (+1). · the question and its options parsed, with trees and pragmatics

Test 5 · ★ · right ✓

In The Jungle Book Kaa hypnotises Mowgli with spinning eyes. What is the real truth?

1. Real snakes cannot hypnotise; they just stare because they have no eyelids — ← Mova's choice · ✓ the right answer · score 9
2. Snakes hypnotise by humming a song — score 5
3. Pythons really can hypnotise children by staring, but only for a few minutes — no support
4. Only old pythons can do it — no support

Why: It took the question to ask what it is done to. It chose option 1 with score 9, against 5 for the next best. Its support: lesson 30, line 4: «In The Jungle Book, Kaa the python hypnotises people with spinning eyes; real snakes can't hypnotise anyone, they just have no eyelids, so their stare never bl…», reached through the same lesson line as the sentence the question matched. What matched: the same action «hypnotise» (+6); the same doer «real snakes» (+3). · the question and its options parsed, with trees and pragmatics

Test 6 · ★ · right ✓

In a cartoon a snake chews its dinner into small bits with big flat teeth. What would a real python do?

1. Cut it into pieces with its spurs first — no support
2. Swallow it whole, usually head first — ← Mova's choice · ✓ the right answer · score 4
3. Suck it up like a drink through a straw — no support
4. Chew it slowly for an hour, like a cow — no support

Why: It took the question to ask what is done. It chose option 2 with score 4, the only option with support. Its support: lesson 87, line 9: «Snakes swallow prey whole; their lower jaw is in two halves joined by stretchy tissue, so the jaws stretch rather than coming «unhinged».», reached through the option's own match among the sentences about the question's things. What matched: it fills the role the question asks for (+2); the same action «swallow» (+1); the same property (+1); a different thing acted on (counts against) (+1). Against it: a different doer (counts against) (-1). · the question and its options parsed, with trees and pragmatics

Test 7 · ★ · right ✓

«ya can't let him go in the woods?? the python's too big for the tank» What is right?

1. Yes, wild snakes will look after it — score 4
2. Yes, snakes always find their way home — no support
3. Yes, a pet python dies within a day outside, so it can do no harm to anything — no support
4. No, a released python can survive and harm wild animals, as in Florida — ← 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 4 for the next best. Its support: lesson 321, line 15: «Burmese pythons let go or escaped from people's homes now live wild in the Everglades of Florida, where they have eaten huge numbers of small mammals and birds…», reached through the same lesson line as the sentence the question matched. What matched: the same action «live» (+4); the same doer «burmese pythons» (+1). · the question and its options parsed, with trees and pragmatics

Test 8 · ★ · right ✓

What would happen if a python squeezed a rat but the rat's heart was still beating?

1. The snake would fall asleep at once — no support
2. The snake would start to chew — no support
3. The snake would let go at once and slide away to find an easier meal — no support
4. The snake would feel it through its coils and keep squeezing — ← Mova's choice · ✓ the right answer · score 6

Why: It took the question to ask what happens next. It chose option 4 with score 6, the only option with support. Its support: lesson 52, line 13: «Pythons ambush their prey after waiting very still, squeeze it so it cannot breathe, and swallow it whole; some snakes sense the warmth of animals with heat pi…», reached through the same lesson line as the sentence the question matched. What matched: the same doer «snakes» (+4); the same action «sense» (+3). Against it: a different thing acted on (counts against) (-1). · the question and its options parsed, with trees and pragmatics

Test 9 · ★ · right ✓

Someone holds a small snake right in front of the camera and stands back. Why does the snake look huge in the photo?

1. Snakes really grow when they are scared — score 2
2. The camera adds metres to snakes — no support
3. Things nearer the camera look bigger than they are — ← Mova's choice · ✓ the right answer · score 9
4. The snake puffs up for photos — no support

Why: It took the question to ask why something happens (its cause). It chose option 3 with score 9, against 2 for the next best. Its support: lesson 321, line 3: «Stories always make big snakes bigger. Old posters show 15-metre monsters swallowing canoes, but a reward for a living snake over about 9 metres was reportedly…», reached through the same lesson line as the sentence the question matched. What matched: the same doer «snake» (+4); the same action «look» (+3); the same property (+2). · the question and its options parsed, with trees and pragmatics

Test 10 · ★ · right ✓

A python has just eaten a deer and lies still for days. What is happening inside?

1. It is getting ready to lay the deer like an egg — score 2
2. It is slowly dying, because the meal was far too big for it — score 2
3. It is shedding all its bones — score 2
4. Its heart and gut have grown bigger to digest the meal — ← Mova's choice · ✓ the right answer · score 3

Why: It took the question to ask which statement is true. It chose option 4 with score 3, against 2 for the next best. Its support: lesson 318, line 5: «Deer antlers fall off every year and grow back; they are bone and can grow over 2 centimetres a day in big deer, and fallen antlers are often gnawed by mice an…», reached through the option's own match among the sentences about the question's things. What matched: the same action «grow» (+3); the same property (+1). Against it: a different doer (counts against) (-1). · the question and its options parsed, with trees and pragmatics

Test 11 · ★ · wrong ✗

«why's a snake shivering, it's cold-blooded innit» What is the best answer?

1. Snakes never move their muscles at all — ← Mova's choice · no support
2. It is scared of the eggs — no support
3. Snakes shiver only when they are ill — no support
4. A python mother twitches her muscles to warm her eggs — ✓ 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 1 · formal language · wrong ✗

Identify the species of snake that is the longest on the basis of reliable measurements.

1. The king cobra, reliably measured at approximately ten metres — no support
2. The reticulated python, reliably measured at approximately seven metres — ✓ the right answer · no support
3. The green anaconda, reliably measured at approximately fifteen metres — ← Mova's choice · score 3
4. The black mamba, reliably measured at approximately nine metres — no support

Why: It took the question to ask which statement is true. It chose option 3 with score 3, the only option with support. Its support: lesson 321, line 9: «No snake anywhere near 15 metres long has ever been measured; a reward offered over a hundred years ago for a living snake longer than about 9 metres was repor…», reached through the option's own match among the sentences about the question's things. What matched: the same action «measure» (+3). The right option, 2, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Exam question 2 · formal language · wrong ✗

Select the response consistent with the established facts concerning the method by which constrictors subdue their prey.

1. The coils crush every bone of the prey at the first contraction, death following from the fractures alone — ← Mova's choice · no support
2. The coils are employed solely for the transport of prey — no support
3. The coils tighten upon each exhalation and principally arrest the circulation of the blood — ✓ the right answer · no support
4. The coils deliver venom through the scales of the snake — 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 · right ✓

Which of the following statements most accurately characterises the small spurs found near the tail of boas and pythons?

1. They are vestiges of the hind limbs of the limbed lizards from which snakes evolved — ← Mova's choice · ✓ the right answer · no support
2. They are newly evolving legs that will lengthen gradually in the course of future generations — no support
3. They are organs for the delivery of venom — no support
4. They are teeth that have migrated along the body — 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 ✓

Ascertain the reason for which a python may survive for many months without food following a large meal.

1. As a cold-blooded animal it expends very little energy — ← Mova's choice · ✓ the right answer · score 5
2. It stores the prey alive within its body — score 0
3. It obtains nourishment from vegetation during this period — no support
4. It ceases all bodily activity until spring — no support

Why: It took the question to ask which statement is true. It chose option 1 with score 5, against 0 for the next best. Its support: lesson 321, line 15: «Burmese pythons let go or escaped from people's homes now live wild in the Everglades of Florida, where they have eaten huge numbers of small mammals and birds…», reached through the same lesson line as the sentence the question matched. What matched: the same action «eat» (+4); the same doer «pythons» (+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/321-big-snakes-pythons-boas-and-anacondas-and-how-big-they-really-get/