---
title: Reef giants and wanderers: whale sharks, mantas, dugongs and sea tur… — how Mova does on the tests · Biology
description: Lesson 174 of the biology course of Mova's primary school: 4 of 11 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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# Reef giants and wanderers: whale sharks, mantas, dugongs and sea turtles

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**Tests:** 4 of 11 right · **Exam:** 1 of 4 right · **Kind:** plain · **Understood:** 10 of 15 · **Run:** 2026-10-18, commit `f3c23ea72`

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Lesson 174 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/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/).

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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/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/).

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### Test 1 · wrong ✗ {#t1}

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In Finding Nemo, Crush the sea turtle surfs a big ocean current. Which part is true?

- **1.** Real turtles can only swim in rivers — **← Mova's choice** · score 3
- **2.** Real turtles never leave one small beach — score 3
- **3.** Real turtles talk like surfers — score 3
- **4.** Real sea turtles ride ocean currents to travel thousands of kilometres — **✓ the right answer** · score 3

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**Why:** It took the question to ask who or what does it. It chose option 1 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 26, line 6: «The blue whale is the largest animal ever known, around 30 metres long and about 150 tonnes or more, with a heart of about 180 kilograms; the water holds up it…», reached through a sentence linked to the one the question matched. What matched: it fills the role the question asks for (+4); the same doer «water» (+3). Against it: a different action (counts against) (-4). The right option, 4, scored 3. · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t1/)

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### Test 2 · right ✓ {#t2}

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In Moana, Tamatoa is a giant crab bigger than a house. What is real?

- **1.** The coconut crab is the largest land crab, but it fits in your arms — **← Mova's choice** · **✓ the right answer** · score 5
- **2.** Coconut crabs are bigger than houses — score 5
- **3.** Coconut crabs live only in the deepest sea trenches of the world — no support
- **4.** There are no real land crabs — no support

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**Why:** It took the question to ask which statement is true. It chose option 1 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 174, line 12: «The coconut crab is the largest land crab in the world, it can climb palm trees, and its pinch is one of the strongest of any animal.», reached through the option's own match among the sentences about the question's things. What matched: the same thing acted on «largest land crab» (+3); the same light verb (be, have, do, get, go) (+2). · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t2/)

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### Test 3 · wrong ✗ {#t3}

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«a coconut crab and 2 turtles, how many legs n flippers»

- **1.** 16 — **← Mova's choice** · no support
- **2.** 14 — no support
- **3.** 12 — no support
- **4.** 18 — **✓ 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/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t3/)

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### Test 4 · wrong ✗ {#t4}

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«4 hammerheads, how many eyes»

- **1.** 16 — **← Mova's choice** · no support
- **2.** 8 — **✓ the right answer** · no support
- **3.** 4 — no support
- **4.** 12 — 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/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t4/)

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### Test 5 · wrong ✗ {#t5}

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«a shark as long as a bus is coming!!! get out» What is right?

- **1.** It must be a blue whale — **← Mova's choice** · no support
- **2.** All big sharks eat people — no support
- **3.** Whale sharks eat boats — no support
- **4.** If it is a whale shark, it eats tiny drifting food and is not hunting people — **✓ 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/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t5/)

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### Test 6 · wrong ✗ {#t6}

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What would happen if a beach where turtles nest got much hotter?

- **1.** The eggs would hatch into crabs — **← Mova's choice** · score 2
- **2.** More of the babies hatching there would be female — **✓ the right answer** · no support
- **3.** All the babies hatching there would be male, every single one — no support
- **4.** Nothing would change — no support

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**Why:** It took the question to ask which statement is true. It chose option 1 with score 2, the only option with support. Its support: lesson 31, line 15: «Many female sea turtles come back to lay eggs on the beach where they hatched; scientists think they remember its magnetic signature.», reached through the option's own match among the sentences about the question's things. What matched: the same action «hatch» (+2). The right option, 2, 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/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t6/)

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### Test 7 · wrong ✗ {#t7}

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«threw my crisp bag in the sea, it's just a bag mate» Why is that harmful?

- **1.** The sea melts plastic in a day — no support
- **2.** Turtles use bags as houses — **← Mova's choice** · score 0
- **3.** Bags turn into fish — no support
- **4.** A turtle may swallow it, thinking it is a jellyfish — **✓ the right answer** · score 0

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**Why:** It took the question to ask why something happens (its cause). It chose option 2 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 174, line 10: «Sea turtles sometimes eat plastic bags, mistaking them for jellyfish; leatherback turtles mostly eat jellyfish and have spines in their throats to hold them.», reached through the option's own match among the sentences about the question's things. The right option, 4, scored 0. · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t7/)

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### Test 8 · right ✓ {#t8}

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«sharks have to keep swimming or they die, all of them» What is right?

- **1.** Yes, sharks never sleep at all — score 3
- **2.** Not all: some reef sharks can rest on the sea floor and still breathe — **← Mova's choice** · **✓ the right answer** · score 5
- **3.** Yes, every shark dies if it stops — no support
- **4.** No, sharks breathe air at the surface — score 4

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**Why:** It took the question to ask which statement is true. It chose option 2 with score 5, against 4 for the next best. Its support: lesson 174, line 11: «Some reef sharks can rest on the sea floor and still breathe, and sharks have been around for hundreds of millions of years, longer than trees.», reached through the option's own match among the sentences about the question's things. What matched: the same place «sea floor» (+3); the same action «rest» (+2). · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t8/)

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### Test 9 · wrong ✗ {#t9}

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A diver sees a small fish fixed to a manta's belly, upside down. What is it?

- **1.** A remora holding on with its sucker — **✓ the right answer** · no support
- **2.** A fish that the manta caught and is carrying — **← Mova's choice** · score 5
- **3.** A baby manta riding along on its back — no support
- **4.** A big barnacle stuck tight to its skin — no support

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**Why:** It took the question to ask what it is done to. It chose option 2 with score 5, the only option with support. Its support: lesson 173, line 11: «Groupers shake their heads at moray eels to invite them to hunt together; the eel goes into cracks and the grouper catches fish that flee into open water.», reached through the option's own match among the sentences about the question's things. What matched: the same action «catch» (+3); it fills the role the question asks for (+1); a different doer (counts against) (+1). 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/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t9/)

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### Test 10 · right ✓ {#t10}

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«dugongs are basically mermaids lol» What is right?

- **1.** They are giant sea turtles — no support
- **2.** Yes, they are half fish and half people — no support
- **3.** They are sea cows that graze sea grass, and sailors may once have mistaken them for mermaids — **← Mova's choice** · **✓ the right answer** · score 6
- **4.** They are a kind of shark — no support

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**Why:** It took the question to ask which statement is true. It chose option 3 with score 6, the only option with support. Its support: lesson 174, line 7: «Dugongs are sea cows that graze on sea grass, and sailors long ago may have mistaken dugongs and manatees for mermaids.», reached through the same lesson line as the sentence the question matched. What matched: the same action «graze» (+4); the same doer «sea cows» (+2). · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t10/)

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### Test 11 · right ✓ {#t11}

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Why might a reef have more room for corals where hawksbill turtles live?

- **1.** Hawksbills eat sponges that would otherwise crowd the corals — **← Mova's choice** · **✓ the right answer** · score -2
- **2.** Hawksbills eat all the fish — no support
- **3.** Hawksbills plant new corals — no support
- **4.** Hawksbills clean the water by filtering it through their big shells — no support

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**Why:** It took the question to ask why something happens (its cause). It chose option 1 with score -2, the only option with support. Its support: lesson 174, line 15: «Hawksbill turtles eat sponges that many other animals cannot eat, and this helps corals have more space to grow.», reached through the option's own match among the sentences about the question's things. Against it: a different doer (counts against) (-2). · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/t11/)

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

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Identify the largest extant species of fish.

- **1.** The great white shark — **← Mova's choice** · no support
- **2.** The blue whale of the open oceans — no support
- **3.** The giant manta ray — no support
- **4.** The whale shark — **✓ 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/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/e1/)

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### Exam question 2 · formal language · wrong ✗ {#e2}

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Which of the following statements most accurately characterises the determination of sex in the offspring of sea turtles?

- **1.** It is fixed by the salinity of the adjacent sea — no support
- **2.** It is determined by the phase of the moon at laying — no support
- **3.** It is governed by the temperature of the sand in which the eggs are incubated — **✓ the right answer** · no support
- **4.** It is determined by the age of the mother — **← Mova's choice** · score 6

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**Why:** It took the question to ask who or what does it. It chose option 4 with score 6, the only option with support. Its support: lesson 143, line 8: «White-tailed deer raise their white tails as they bound away, warning others and helping fawns follow; the book's Bambi was a European roe deer, the film's a w…», reached through the same lesson line as the sentence the question matched. What matched: it fills the role the question asks for (+4); the same doer «film» (+3). Against it: a different thing acted on (counts against) (-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/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/e2/)

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

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Ascertain the principal reason for which sea turtles are observed to ingest plastic bags.

- **1.** Plastic is a necessary component of their diet — **← Mova's choice** · no support
- **2.** The bags are mistaken for jellyfish, upon which certain turtles feed — **✓ the right answer** · no support
- **3.** Ingestion occurs exclusively during sleep — no support
- **4.** The bags are employed in the construction of nests — 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/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/e3/)

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### Exam question 4 · formal language · right ✓ {#e4}

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Select the response consistent with the established facts concerning the sucker of the remora.

- **1.** It is a modified fin by which the fish attaches itself to sharks and rays — **← Mova's choice** · **✓ the right answer** · score 5
- **2.** It is an adhesive gland secreting a glue — no support
- **3.** It is a set of hooked teeth — no support
- **4.** It is an organ borrowed from the host shark and retained throughout the life of the fish — no support

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**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 174, line 16: «Remoras stick to sharks and rays with a sucker on their heads, and that sucker is really a changed fin.», reached through the option's own match among the sentences about the question's things. What matched: the same thing acted on «changed fin» (+3); the same light verb (be, have, do, get, go) (+2). · [the question and its options parsed, with trees and pragmatics](https://md.mova.elamur.ai/free/en/corpora/questions/biology/174-reef-giants-and-wanderers-whale-sharks-mantas-dugongs-and-sea-turtles/e4/)

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- ← previous: [173. Coral reef partners and tricksters: clownfish, c…](https://md.mova.elamur.ai/free/en/school-run/biology/173-coral-reef-partners-and-tricksters-clownfish-cleaners-mimics-and-puffers/)
- next →: [175. The twilight zone: barreleyes, lanternfish and t…](https://md.mova.elamur.ai/free/en/school-run/biology/175-the-twilight-zone-barreleyes-lanternfish-and-the-biggest-daily-journey-on-earth/)
- ↑ back to [Biology](https://md.mova.elamur.ai/free/en/school-run/biology/)