The Tardigrades Lecture listening test page gives you Section 4 of Cambridge IELTS 19 Listening Test 2 in full: the official answer key for Questions 31–40, playable audio, an explanation for every question with the exact transcript line that proves it, and the complete recording script. The lecture introduces tardigrades, the near-microscopic ‘water bears’ and ‘moss piglets’ that survive freezing, boiling and drought, covering their bodies and claws, their habitats, the tun state of cryptobiosis, their liquid diet and their conservation status. All ten questions are note completion under a strict ONE WORD ONLY limit, and the notes compress the speaker’s full sentences into short noun phrases. Predict the word class of each gap with the note completion strategy in the preparation pause, then check every answer on the complete Cambridge IELTS 19 Listening Test 2 answers page covering all four sections.

Listening Audio — Section 4

Play the recording once, without pausing, and answer Questions 31–40 before you check the key. In the real exam you hear each section exactly once.

Questions 31–40

Questions 31–40

Complete the notes below.

Write ONE WORD ONLY for each answer.

– more than 1,000 species, 0.05–1.2 millimetres long

– absence of respiratory organs

– often found at the bottom of a lake or on plants

– In dry conditions, they roll into a ball called a ‘tun’.

– They stay alive with a much lower metabolism than usual.

– may eat other tardigrades

• Tardigrades
• – also known as water ‘bears’ (due to how they 31 ………… ) and ‘moss piglets’
• Physical appearance
• – a 32 ………… round body and four pairs of legs
• – claws or 33 ………… for gripping
• – body filled with a liquid that carries both 34 ………… and blood
• – mouth shaped like a 35 ………… with teeth called stylets
• Habitat
• – very resilient and can exist in very low or high 36 …………
• Cryptobiosis
• – A type of 37 ………… ensures their DNA is not damaged.
• – Research is underway to find out how many days they can stay alive in 38 …………
• Feeding
• – consume liquids, e.g., those found in moss or 39 …………
• Conservation status
• – They are not considered to be 40 ………… .

Tardigrades Lecture Listening Answers

Questions and Answers

Tardigrades Lecture Answer Explanations

31. move — the note explains the name water ‘bears’, and the lecture gives the reason: “‘bear’ because of the way they move”. Thrive is the trap, because water refers to where they thrive best and the bear half of the name is about motion.

32. short — the body note needs an adjective before round, and the lecture supplies it: “They have a body which is short, and also rounded”. Barrel is the comparison the speaker draws, not the describing word the note requires.

33. discs — the gripping note pairs claws with a second feature: “some species don’t have any claws: what they have are discs”. Suction names how the discs work, so the plural noun after claws or is the answer.

34. oxygen — the fluid note asks what it carries besides blood: “oxygen and also blood are transported in a fluid”. Lungs is the trap, because the lecture stresses there are no lungs at all.

35. tube — the mouth note asks for its shape: “The tardigrade’s mouth is a kind of tube that can open outwards”. Stylets fails because the notes already print the name of the teeth, leaving the shape word for the gap.

36. temperatures — the habitat note ends in very low or high ……, and the lecture confirms they are “able to withstand temperatures as low as minus ~200 degrees centigrade, or highs of more than 148 degrees centigrade”. Radiation and pressure are other survival feats, so the plural noun after high is temperatures.

37. protein — the cryptobiosis note asks what protects the DNA: “tardigrades produce a protein that protects their DNA”. Cryptobiosis itself fails because the notes use that word as the heading, not the answer.

38. space — the research note asks where survival days are being counted: “several tests taking place in space, to determine how long tardigrades might be able to survive there”. Decades is the trap, because that is the tun duration on Earth, not the venue of the tests.

39. seaweed — the feeding note pairs moss with a second source: “They suck the juices from moss, or extract fluid from seaweed”. Moss is already printed in the note, so the noun after or completes the line.

40. endangered — the final note states their conservation standing: tardigrades “are not on any endangered list”. Thriving is the opposite claim made by researchers, so the adjective after to be is endangered.

Listening Transcript — Section 4

For my project on invertebrates, I chose to study tardigrades. These are microscopic — or to be more precise — near-microscopic animals. There are well over a thousand known species of these tiny animals, which belong to the phylum Tardigrada. Most tardigrades range in length from 0.05 to 1 millimetre, though the largest species can grow to be 1.2 millimetres in length. They are also sometimes called ‘water bears’: ‘water’ because that’s where they thrive best, and ‘bear’ because of the way they move. ‘Moss piglet’ is another name for tardigrades because of the way they look when viewed from the front. They were first discovered in Germany in 1773 by Johann Goeze, who coined the name Tardigrada.

As I say, there are many different species of tardigrade — too many to describe here — but, generally speaking, the different species share similar physical traits. They have a body which is short, and also rounded- a bit like a barrel- and the body comprises four segments. Each segment has a pair of legs, at the end of which are between four and eight sharp claws. I should also say that some species don’t have any claws: what they have are discs, and these work by means of suction. They enable the tardigrade to cling to surfaces or to grip its prey. Within the body, there are no lungs, or any organs for breathing at all. Instead, oxygen and also blood are transported in a fluid that fills the cavity of the body.

As far as the tardigrade’s head is concerned, the best way I can describe this is that it looks rather strange — a bit squashed even — though many of the websites I looked at described its appearance as cute, which isn’t exactly very scientific. The tardigrade’s mouth is a kind of tube that can open outwards to reveal teeth-like structures known as ‘stylets’. These are sharp enough to pierce plant or animal cells.

So, where are tardigrades found? Well, they live in every part of the world, in a variety of habitats: most commonly, on the bed of a lake, or on many kinds of plants or in very wet environments. There’s been some interesting research which has found that tardigrades are capable of surviving radiation and very high pressure, and they’re also able to withstand temperatures as low as minus ~200 degrees centigrade, or highs of more than 148 degrees centigrade, which is incredibly hot.

It has been said that tardigrades could survive long after human beings have been wiped out, even in the event of an asteroid hitting the earth. If conditions become too extreme and tardigrades are at risk of drying out, they enter a state called cryptobiosis. They form a little ball, called a tun — that’s T-U-N — by retracting their head and legs, and their metabolism drops to less than one percent of normal levels. They can stay in this state for decades, and if re-introduced to water, when they will come back to life in a matter of a few hours. While in this state of cryptobiosis, tardigrades produce a protein that protects their DNA. In 2016, scientists revived two tardigrades that had been tuns for more than 30 years. There was a report that,in 1948, a 120-year-old tun was revived, but this experiment has never been repeated. There are currently several tests taking place in space, to determine how long tardigrades might be able to survive there. I believe the record so far is 10 day.

So, erm, moving on. In terms of their diet, tardigrades consume liquids in order to survive. Although they have teeth, they don’t use these for chewing. They suck the juices from moss, or extract fluid from seaweed, but some species prey on other tardigrades, from other species or within their own. I suppose this isn’t surprising, given that tardigrades are mainly comprised of liquid and are coated with a type of gel.

Finally, I’d like to mention the conservation status of tardigrades. It is estimated that they have been in existence for approximately half a billion years and, in that time, they have survived five mass extinctions. So, it will probably come as no surprise to you, that tardigrades have not been evaluated by the International Union for Conservation of Nature and are not on any endangered list. Some researchers have described them as thriving.

Does anyone have any questions they’d like to ask?

Key Vocabulary and Spelling

Study Tips

Respect the ONE WORD ONLY limit on every line of this task. Question 38 scores with space, never with “in space”, and Question 39 with seaweed alone, because a preposition pushed into the gap breaks the rule and loses the mark. Check the limit as part of your note completion strategy routine during the preparation pause, and count words again while transferring.

The notes paraphrase the lecture at every turn, so prepare the synonym pairs in advance. How they …… stands for “the way they move”, both …… and blood stands for “oxygen and also blood”, and not considered to be …… stands for “are not on any endangered list”. When the speaker’s sentence sounds nothing like the note, the paraphrase is doing its job, so hold your predicted word class and wait for the exact noun or adjective that fills it.

The lecture runs ten questions without a pause, and the gaps cluster around dense lists of figures: 0.05 to 1.2 millimetres, minus ~200 and 148 degrees centigrade, 30 years and 120 years. None of those numbers is an answer here, so keep your pen on the note headings instead of the digits, and run the final spelling check on cryptobiosis, metabolism and endangered against the listening spelling rules list.

Practice More Listening Tests

Mark the ten answers, reread the explanation for each miss, and add the result to your record on the full Cambridge IELTS 19 Listening Test 2 answers page, which collects the keys, explanations and transcripts for all four sections. The free IELTS listening practice course from Simply IELTS builds the lecture skills this section demands: ten unbroken questions, heavy paraphrase and a strict word limit. Then try this interactive listening test: labyrinths for another ten-question lecture under exam conditions, and revisit the Section 2 lifeboat volunteer talk and the Section 3 recycling footwear discussion to close out the full paper.