---
title: Identify the means by which pit vipers detect warm-blooded prey in c… — Hidden senses: magnetic birds and turt… · tree and pragmatics
description: Identify the means by which pit vipers detect warm-blooded prey in conditions of total darkness. Exam question 1 of lesson 232 «Hidden senses: magnetic birds and turtles, ultraviolet bees, heat-seeing snakes, whiskers and lateral lines» of the biology course of Mova's primary school, with the depend
---

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# Exam question 1 · Hidden senses: magnetic birds and turtles, ultraviolet bee…

<!-- .ven lang=en -->
Identify the means by which pit vipers detect warm-blooded prey in conditions of total darkness.

<!-- .vintro -->
**Mova's choice:** option 3 · **The right answer:** option 3 · right ✓ · **Who acts:** you, the, pit vipers · **What happens:** identify, mean, detect, condition · **To what, where:** blooded prey, conditions, total darkness · **Speech:** someone speaks here

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This is exam question 1 of lesson 232 «Hidden senses: magnetic birds and turtles, ultraviolet bees, heat-seeing snakes, whiskers and lateral lines» of the biology course of Mova's primary school, asked in stiff, formal language. The page gives the question's syntax tree — a dependency tree in the style of Universal Dependencies — and its pragmatics clause by clause, then the 4 options as the student saw them, each with its tree and pragmatics. Every text is parsed by Mova itself. How the student answered it, with the score of every option and why: [the test at school](https://md.mova.elamur.ai/free/en/school-run/biology/232-hidden-senses-magnetic-birds-ultraviolet-bees-heat-seeing-snakes/#e1).

## The question {#question}

```conllu
# sent_id = question:biology:232-hidden-senses-magnetic-birds-ultraviolet-bees-heat-seeing-snakes:e1:1
# text = Identify the means by which pit vipers detect warm-blooded prey in conditions of total darkness.
1	Identify	identify	VERB	VB	Mood=Imp|VerbForm=Fin	0	root	_	_
2	the	the	DET	DT	Definite=Def|PronType=Art	3	nsubj	_	_
3	means	mean	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	1	ccomp	_	_
4	by	by	ADP	IN	_	5	case	_	_
5	which	which	PRON	WDT	PronType=Rel	8	obl	_	_
6	pit	pit	NOUN	NN	Number=Sing	7	compound	_	_
7	vipers	viper	NOUN	NNS	Number=Plur	8	nsubj	_	_
8	detect	detect	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	3	ccomp	_	_
9	warm	warm	ADJ	JJ	Degree=Pos	11	amod	_	SpaceAfter=No
10	-	-	PUNCT	HYPH	_	9	punct	_	SpaceAfter=No
11	blooded	blooded	ADJ	JJ	Degree=Pos	12	amod	_	_
12	prey	prey	NOUN	NN	Number=Sing	8	obj	_	_
13	in	in	ADP	IN	_	14	case	_	_
14	conditions	condition	NOUN	NNS	Number=Plur	8	obl	_	_
15	of	of	ADP	IN	_	17	case	_	_
16	total	total	ADJ	JJ	Degree=Pos	17	amod	_	_
17	darkness	darkness	NOUN	NN	Number=Sing	14	nmod	_	SpaceAfter=No
18	.	.	PUNCT	.	_	1	punct	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **identify** | imperative | you *not said here* |  |  |  |  |  | vn characterize-29.2-1-1 «NP V S\_ING»: agent=Agent clause=Theme |
| 2 | **mean** | present | the |  |  |  |  |  | vn intend-61.2-1 «NP V S»: agent=Agent clause=Topic |
| 3 | **detect** | present | pit vipers | blooded prey |  | conditions of total darkness |  |  | vn see-30.1-1 «NP V S»: agent=Experiencer prey=Stimulus |
| 4 | **condition** |  |  | total darkness |  |  |  |  | nom condition «state transitive»: of=patient |

<!-- .note -->
One row per clause the reader finds. «not said here»: a role filled from the clause above. «roles by»: a VerbNet class and frame when one fits the verb, else the reader's rules on the tree.

## The options {#options}

### Option 1 {#o1}

<!-- .ven lang=en -->
Electric receptors situated upon the forked tongue

```conllu
# sent_id = question:biology:232-hidden-senses-magnetic-birds-ultraviolet-bees-heat-seeing-snakes:e1:o1:1
# text = Electric receptors situated upon the forked tongue
1	Electric	electric	ADJ	JJ	Degree=Pos	2	amod	_	_
2	receptors	receptor	NOUN	NNS	Number=Plur	0	root	_	_
3	situated	situate	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	2	acl	_	_
4	upon	upon	ADP	IN	_	7	case	_	_
5	the	the	DET	DT	Definite=Def|PronType=Art	7	det	_	_
6	forked	fork	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	7	amod	_	_
7	tongue	tongue	NOUN	NN	Number=Sing	3	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **situate** | participle |  | Electric receptors *not said here* |  | the forked tongue |  |  | vn put-9.1 «NP V NP PP.destination»: agent=Agent upon tongue=Destination |
| 2 | **fork** | participle |  |  |  |  |  |  | vn pocket-9.10 «NP V NP.theme»: agent=Agent |

### Option 2 {#o2}

<!-- .ven lang=en -->
Detection of prey by sight alone

```conllu
# sent_id = question:biology:232-hidden-senses-magnetic-birds-ultraviolet-bees-heat-seeing-snakes:e1:o2:1
# text = Detection of prey by sight alone
1	Detection	detection	NOUN	NN	Number=Sing	0	root	_	_
2	of	of	ADP	IN	_	3	case	_	_
3	prey	prey	NOUN	NN	Number=Sing	1	nmod	_	_
4	by	by	ADP	IN	_	5	case	_	_
5	sight	sight	NOUN	NN	Number=Sing	1	nmod	_	_
6	alone	alone	ADV	RB	_	5	advmod	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **detect** |  | sight | prey |  |  |  |  | nom detection «cognition transitive»: of=patient by=agent |

### Option 3 · ← Mova's choice · ✓ the right answer {#o3}

<!-- .ven lang=en -->
Heat-sensitive pits situated upon the face

```conllu
# sent_id = question:biology:232-hidden-senses-magnetic-birds-ultraviolet-bees-heat-seeing-snakes:e1:o3:1
# text = Heat-sensitive pits situated upon the face
1	Heat	heat	NOUN	NN	Number=Sing	3	compound	_	SpaceAfter=No
2	-	-	PUNCT	HYPH	_	1	punct	_	SpaceAfter=No
3	sensitive	sensitive	ADJ	JJ	Degree=Pos	4	amod	_	_
4	pits	pit	NOUN	NNS	Number=Plur	0	root	_	_
5	situated	situate	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	4	acl	_	_
6	upon	upon	ADP	IN	_	8	case	_	_
7	the	the	DET	DT	Definite=Def|PronType=Art	8	det	_	_
8	face	face	NOUN	NN	Number=Sing	5	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **situate** | participle |  | sensitive pits *not said here* |  | the face |  |  | vn put-9.1 «NP V NP PP.destination»: agent=Agent upon face=Destination |

### Option 4 {#o4}

<!-- .ven lang=en -->
Echolocation by means of clicks

```conllu
# sent_id = question:biology:232-hidden-senses-magnetic-birds-ultraviolet-bees-heat-seeing-snakes:e1:o4:1
# text = Echolocation by means of clicks
1	Echolocation	echolocation	NOUN	NN	Number=Sing	3	nsubj	_	_
2	by	by	ADP	IN	_	1	fixed	_	_
3	means	mean	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
4	of	of	ADP	IN	_	5	case	_	_
5	clicks	click	NOUN	NNS	Number=Plur	3	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **mean** | present | Echolocation |  |  |  |  | of clicks | vn intend-61.2-1 «NP V S»: agent=Agent |

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**Text:** the tests of Mova's primary school, written for Mova (`world/data/school/`), as the course runner gave them to the student. **Trees:** Mova's own parse — the `en` model on the CPU, when the site is built — not checked by a teacher; they may be wrong. **Frames:** Mova's frames reader (`prag`), each text read on its own. Elamur Cosmic License.

<!-- /div -->

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- next →: [Hidden senses: magnetic birds and turt…, exam 2](https://md.mova.elamur.ai/free/en/corpora/questions/biology/232-hidden-senses-magnetic-birds-ultraviolet-bees-heat-seeing-snakes/e2/)
- ↑ back to [Hidden senses: magnetic birds and turtles, ultraviolet bees, heat-seeing snakes, whiskers and lateral lines](https://md.mova.elamur.ai/free/en/corpora/questions/biology/232-hidden-senses-magnetic-birds-ultraviolet-bees-heat-seeing-snakes/)