The secret of staying young: reading answers and analysis
Biologist Ysabel Giraldo found that worker ants of the species Pheidole dentata show no sign of ageing. Old ants cared for the young, followed trails and attacked prey as well as young ones, and their brains showed no decline.
Both blocks follow the passage in order. The notes (1-8) cover paragraphs 3 to 5: the age groups, the behaviour tests, then the brain tests. The TRUE / FALSE / NOT GIVEN statements (9-13) start in paragraph 2 and end in paragraph 7.
Answer key and self-check
Type what you wrote and hit mark. Hide the key first if you haven't done the passage yet. Every question number jumps to its explanation.
How to attack this block: The notes follow Giraldo's tests in the order the passage describes them. Gap 5 needs an adverb after 'how', so take the -ly word. Gaps 6 to 8 are in the brain paragraph and each needs a noun; two of them must be plural.
Question 1
Answer: fourParagraph 3, second sentence
Also accepted: 4
How many age groups of ants did Giraldo study?
Giraldo focused on ants at four age ranges: 20 to 22 days, 45 to 47 days, 95 to 97 days and 120 to 122 days.
Question says → Passage says
Focused on a total ofGiraldo focused on ants at
different age groupsage ranges
Why: 'Age ranges' is 'age groups', and she studied four of them. The four ranges are listed straight after, so you can count to check. The key accepts 'four' or '4'.
The trap: '140' (the typical lifespan) is in the sentence before, and some people write 'two' from the 20-day and 95-day comparison later. The total is four.
Question 2
Answer: youngParagraph 4, first sentence
What did the ants look after?
Giraldo watched how well the ants took care of the young of the colony
Question says → Passage says
how well ants looked after theirhow well the ants took care of the
Why: 'Took care of' is 'looked after', and what they cared for is 'the young'. Here 'young' works as a noun meaning baby ants.
The trap: 'Colony' follows in the same phrase, but the ants look after the young of the colony, not the colony itself.
Question 3
Answer: foodParagraph 4, second sentence
What did the ants find by following a scent trail?
the telltale scent that the insects usually leave to mark a trail to food
Question says → Passage says
their ability to locatehow well 20-day-old and 95-day-old ants followed
using a scent trailthe telltale scent… to mark a trail to
Why: The scent marks a trail to food, so following it means finding food. The gap needs a noun after 'locate'.
The trap: 'Prey' comes later in the paragraph, but that's a separate test with a live fruit fly, not the scent trail.
Question 4
Answer: lightParagraph 4, third sentence
Which stimulus did Giraldo test the ants' reactions to?
She tested how ants responded to light
Question says → Passage says
the effect that ___ had on themhow ants responded to
Why: Testing how ants responded to light is testing the effect light had on them. The gap needs a noun subject for 'had'.
The trap: 'Activity' is measured in the same sentence, but that's a separate test, and 'the effect that activity had on them' doesn't match.
Question 5
Answer: aggressivelyParagraph 4, last sentence
In what way did the ants attack prey?
the older ants attacked the poor fruit fly just as aggressively as the young ones did
Question says → Passage says
how ___ they attacked preyattacked the poor fruit fly just as aggressively
preya tethered fruit fly
Why: The gap follows 'how' and comes before 'they attacked', so it needs an adverb describing the attack. The passage says 'aggressively'. Spell it with a double g and double s.
The trap: 'Active' appears earlier in the paragraph, but it's an adjective about general movement, not how they attacked.
Question 6
Answer: locationParagraph 5, second sentence
Which feature of the dying brain cells did Giraldo compare across ages?
She saw no major differences with age, nor was there any difference in the location of the dying cells
Question says → Passage says
comparison between age and theno major differences with age, nor… any difference in the
dying cellsthe dying cells / cells that were Close to death
Why: Giraldo checked whether age changed the location of the dying cells. The note keeps 'of dying cells', so the gap is the noun before it: 'location'.
The trap: 'Number' feels natural, but the passage's second comparison is specifically about location. 'Functions' comes later and isn't followed by 'of dying cells'.
Question 7
Answer: neuronsParagraph 5
What comes together in synaptic complexes?
the density of synaptic complexes within these structures-regions where neurons come together
Question says → Passage says
areas in which ___ meetregions where neurons come together
Why: 'Regions' becomes 'areas', and 'come together' becomes 'meet'. The things that meet are neurons. It must be plural.
The trap: 'Cells' is a fair guess from the previous sentences, but the passage names neurons here, and 'neurons' is the word to copy.
Question 8
Answer: chemicalsParagraph 5
What were the two things in the brain linked to ageing?
the old ants didn't experience any drop in the levels of either serotonin or dopamine-brain chemicals whose decline often coincides with aging
Question says → Passage says
level of twothe levels of either serotonin or dopamine
associated with ageingwhose decline often coincides with aging
Why: Serotonin and dopamine are described as 'brain chemicals' whose decline goes with ageing. The note says 'level of two ___', so the gap is the general noun: 'chemicals'.
The trap: Don't write 'serotonin' or 'dopamine'. The note needs one word covering both, and only 'chemicals' does that.
TRUE / FALSE / NOT GIVEN
Questions 9-13
How to attack this block: Read each statement for its strong word: 'only known animals', 'first', 'as she had predicted'. The naked mole rat and Giraldo's own expectations give two clear FALSE answers. The bee studies are mentioned, but not how they measured decline.
Question 9
Answer: FALSEParagraph 2, first two sentences
Are these ants the only known animals that stay active almost all their lives?
Naked mole rats can live for almost 30 years and stay fit for nearly their entire lives.
Question says → Passage says
remain active for almost their whole livesstay fit for nearly their entire lives
Why: FALSE. Naked mole rats also stay fit for nearly their whole lives, so the ants aren't the only ones.
The trap: 'Such age-defying feats are rare' tempts people to say TRUE. Rare doesn't mean unique, and the next sentence gives another example.
Question 10
Answer: TRUEParagraph 3, third sentence
Was Giraldo the first to study these ants knowing their exact ages?
Unlike all previous studies, which only estimated how old the ants were, her work tracked the ants from the time the pupae became adults, so she knew their exact ages.
Question says → Passage says
the first personUnlike all previous studies
precise data about the insects' agesshe knew their exact ages
Why: TRUE. All earlier studies only estimated ages, but Giraldo tracked the ants from adulthood and knew exactly how old they were. That makes her the first to use precise age data.
The trap: Paragraph 6 says this is the first time anyone has looked at behaviour and brains so thoroughly, which is a different 'first'. Both are true, but the age point is in paragraph 3.
Question 11
Answer: FALSEParagraph 4
Did the ants behave as Giraldo had expected?
Giraldo expected the older ants to perform poorly in all these tasks. But the elderly insects were all good caretakers and trail-followers
Question says → Passage says
as she had predictedGiraldo expected the older ants to perform poorly
behavedwere all good caretakers and trail-followers
Why: FALSE. She expected the old ants to do badly, but they did well, so they didn't behave as she predicted. The 'But' marks the contradiction.
Question 12
Answer: NOT GIVENParagraph 6
Did the recent bee studies use different ways of measuring decline?
the results of recent bee studies were mixed-some studies showed age-related declines, which biologists call senescence, and others didn't
Question says → Passage says
The recent studies of beesrecent bee studies
age-related declineage-related declines
Why: NOT GIVEN. The passage gives the bee studies' results (mixed), but says nothing about the methods they used.
The trap: Mixed results might suggest different methods, but that's your guess, not the passage's statement.
Question 13
Answer: TRUEParagraph 7, second sentence
Do ants in the lab tend to live longer than those in the wild?
Out in the wild, the ants probably don't live for a full 140 days thanks to predators, disease and just being in an environment that's much harsher than the comforts of the lab.
Question says → Passage says
kept in laboratory conditionsthe comforts of the lab
tend to live longer livesIn the lab, P dentata worker ants typically live for around 140 days
Why: TRUE. Lab ants typically live about 140 days, while wild ants 'probably don't' reach that because of predators, disease and harsh conditions. So lab ants tend to live longer.
The trap: 'Probably' makes some people choose NOT GIVEN, but the statement only says 'tend to', which matches the passage's level of certainty.
TRUE. In the wild the ants probably don't reach 140 days, so the lab ants live longer.
Words from this passage worth keeping
age-defying(Paragraph 2)
seeming not to be affected by getting older
deteriorate(Paragraph 2)
get gradually worse
telltale(Paragraph 4)
revealing or giving a clear sign of something
tethered(Paragraph 4)
tied so it can't move far
coincide with(Paragraph 5)
happen at the same time as
senescence(Paragraph 6)
the process of deteriorating with age
harsh(Paragraph 7)
difficult and unpleasant to live in
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The full Cambridge 14 Test 4 reading paper: all three passages, 60 minutes, marked the second you finish with a review of every answer. Already done it? Take it again and see if the same traps still get you.
Cambridge IELTS 14, Test 4, Reading Passage 1. The passage and questions belong to Cambridge University Press and are not reproduced here. We quote short extracts only as evidence for our own commentary, and the answers are published for self-marking. Get the book for the full text, or sit the test on Langujet.
The rest of Cambridge 14 Test 4
Passage 1 · Questions 1-13 · You're hereThe secret of staying young
