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Plant Thermometer Trigger Reading Answers: IELTS Reading Practice Test

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Updated on Jul 02, 2024, 11:57

The IELTS Reading section is designed to assess your reading skills in English and will be put to the test. Across three passages, you'll encounter a variety of texts that aim to evaluate your ability to comprehend and interpret written information. With 40 questions in total, this section covers diverse topics and genres, challenging you to demonstrate skills such as skimming, scanning, and understanding implicit meanings within a time limit of 60 minutes.

 

In the "Plant Thermometer Trigger" passage, you'll explore the fascinating world of plant biology and the mechanisms behind how plants respond to temperature changes. Discover how plants utilise a molecular 'thermometer' to sense temperature fluctuations, triggering adaptive responses crucial for their survival and growth. This passage sheds light on the intricate processes within plant physiology and the remarkable strategies they employ to thrive in diverse environmental conditions.
 

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1. Plant Thermometer Trigger Reading Passage

You should spend approximately 20 minutes answering Questions 1 - 13 based on the Reading Passage below. This approach can help manage time effectively during a reading comprehension activity or exam.   

                           

A photoreceptor molecule in plant cells has been found to have a second job as a thermometer after dark – allowing plants to read seasonal temperature changes. Scientists say the discovery could help breed crops that are more resilient to the temperatures expected to result from climate change


 

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2. Plant Thermometer Trigger Reading Questions with Answers

Discover exciting and informative IELTS reading answers about Plant Thermometer Trigger

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1.

Plant Thermometer Trigger Reading Passage

General Instructions
General Instructions for IELTS Reading:

  • You will have 60 minutes to complete the entire reading test.
  • The test consists of three reading passages with a total of 40 questions.
  • The texts may be taken from books, magazines, journals, or newspapers.
  • You will receive an answer sheet and should write your answers on it.
  • The questions will be in different formats, such as multiple-choice, matching, sentence completion, and summary completion.
  • The reading passages will increase in difficulty as you progress through the test.
  • You cannot bring any electronic devices, including mobile phones, into the test room.

 

 

 

 

Plant Thermometer Trigger Reading Passage

 

Paragraph A

An international team of scientists led by the University of Cambridge has discovered that the ‘thermometer’ molecule in plants enables them to develop according to seasonal temperature changes. Researchers have revealed that molecules called phytochromes – used by plants to detect light during the day – actually change their function in darkness to become cellular temperature gauges that measure the heat of the night.
The new findings, published in the journal Science, show that phytochromes control genetic switches in response to temperature as well as light to dictate plant development.

 

Paragraph B

At night, these molecules change states, and the pace at which they change is ‘directly proportional to temperature’, say scientists who compare phytochromes to mercury in a thermometer. The warmer it is, the faster the molecular change – stimulating plant growth.

 

Paragraph C

Farmers and gardeners have known for hundreds of years how responsive plants are to temperature: warm winters cause many trees and flowers to bud early, something humans have long used to predict weather and harvest times for the coming year. The latest research pinpoints for the first time a molecular mechanism in plants that reacts to temperature – often triggering the buds of spring we long to see at the end of winter.

 

Paragraph D

With weather and temperatures set to become ever more unpredictable due to climate change, researchers say the discovery that this light-sensing molecule also functions as the internal thermometer in plant cells could help us breed tougher crops. ‘It is estimated that agricultural yields will need to double by 2050, but climate change is a major threat to achieving this. Key crops such as wheat and rice are sensitive to high temperatures. Thermal stress reduces crop yields by around 10% for every one-degree increase in temperature,’ says lead researcher Dr. Philip Wigge from Cambridge’s Sainsbury Laboratory. ‘Discovering the molecules that allow plants to sense temperature has the potential to accelerate the breeding of crops resilient to thermal stress and climate change.’

 

Paragraph E

In their active state, phytochrome molecules bind themselves to DNA to restrict plant growth. During the day, sunlight activates the molecules, slowing down growth. If a plant finds itself in the shade, phytochromes are quickly inactivated – enabling it to grow faster to find sunlight again. This is how plants compete to escape each other’s shade. ‘Light-driven changes to phytochrome activity occur very fast, in less than a second,’ says Wigge.
At night, however, it’s a different story. Instead of a rapid deactivation following sundown, the molecules gradually change from their active to inactive state. This is called ‘dark reversion’. ‘Just as the mercury rises in a thermometer, the rate at which phytochromes revert to their inactive state during the night is a direct measure of temperature,’ says Wigge.

 

Paragraph F

‘The lower the temperature, the slower the rate at which phytochromes revert to inactivity, so the molecules spend more time in their active, growth-suppressing state. This is why plants grow slower in winter. Warm temperatures accelerate dark reversion so that phytochromes rapidly reach an inactive state and detach themselves from the plant’s DNA – allowing genes to be expressed and plant growth to resume.’ Wigge believes phytochrome thermo-sensing evolved at a later stage, and co-opted the biological network already used for light-based growth during the downtime of night.

 

Paragraph G

Some plants mainly use day length as an indicator of the reason. Other species, such as daffodils, have considerable temperature sensitivity and can flower months in advance during a warm winter. In fact, the discovery of the dual role of phytochromes provides the science behind a well-known rhyme long used to predict the coming season: oak before ash we’ll have a splash, ash before oak we’re in for a soak.
Wigge explains: ‘Oak trees rely much more on temperature, likely using phytochromes as thermometers to dictate development, whereas ash trees rely on measuring day length to determine their seasonal timing. A warmer spring, and consequently a higher likeliness of a hot summer, will result in oak leafing before ash. A cold spring will see the opposite. As the British know only too well, a colder summer is likely to be a rain-soaked one.’

 

Paragraph H

The new findings are the culmination of twelve years of research involving scientists from Germany, Argentina, and the US, as well as the Cambridge team. The work was done in a model system using a mustard plant called Arabidopsis, but Wigge says the phytochrome genes necessary for temperature sensing are found in crop plants as well. ‘Recent advances in plant genetics now mean that scientists are able to rapidly identify the genes controlling these processes in crop plants, and even alter their activity using precise molecular “scalpels”,’ adds Wigge. ‘Cambridge is uniquely well-positioned to do this kind of research as we have outstanding collaborators nearby who work on more applied aspects of plant biology and can help us transfer this new knowledge into the field.’
 

Also Read: IELTS Reading Tips & Tricks

2.

Plant Thermometer Trigger Reading Questions and Answers

Discover exciting and informative IELTS reading answers about Plant Thermometer Trigger

Questions and Answers 1-6
Complete the table below.

  • Do the following statements agree with the information given in the Reading Passage?
  • In boxes 1-6 on your answer sheet, write -
  • TRUE if the statement agrees with the information
  • FALSE if the statement contradicts the information
  • NOT GIVEN if there is no information on this

 

1. The Cambridge scientists’ discovery of the ‘thermometer molecule’ caused surprise among other scientists.

2. The target for agricultural production by 2050 could be missed.

3. Wheat and rice suffer from a rise in temperatures.

4. It may be possible to develop crops that require less water.

5. Plants grow faster in sunlight than in shade.

6. Phytochromes change their state at the same speed day and night.

 

Plant Thermometer Trigger Reading Answers with Explanations (1-5)

 

Type of question: True/False/Not Given

In this question type, you are required to determine whether the statements provided agree with, contradict, or are not mentioned in the reading passage.  

 

 

How to best answer: 

  • Understand what information is being presented and what is being asked.
  • Find relevant information in the reading passage that relates to the statement.
  • Determine if the statement agrees with, contradicts, or is not mentioned in the passage.
  • If the information is not explicitly provided in the passage, select 'Not Given' rather than making assumptions.
  • Base your answers solely on the information presented in the passage, avoiding personal opinions or outside knowledge.

 

1. Not given

 

Reference:

 

From paragraph: N.A.


Explanation

The passage does not mention any reaction or response from other scientists regarding the Cambridge scientists' discovery of the 'thermometer molecule', so it cannot be determined whether it caused surprise or not.


 

2. True

 

 

Reference:

 

From paragraph D: "It is estimated that agricultural yields will need to double by 2050, but climate change is a major threat to achieving this."


 

Explanation

The passage explicitly states that climate change poses a significant threat to achieving the target for agricultural production by 2050, implying that it could be missed.


 

3. True

 

 

Reference:

 

From paragraph D: “Key crops such as wheat and rice are sensitive to high temperatures. Thermal stress reduces crop yields by around 10% for every one-degree increase in temperature,’ says lead researcher Dr Philip Wigge from Cambridge’s Sainsbury Laboratory.”


Explanation

Paragraph D provides clear evidence that wheat and rice are sensitive to high temperatures, which can result in reduced crop yields.

 

 

4. Not given

 

Reference:

From paragraph: N.A.

 

Explanation

The passage does not contain any information about the possibility of developing crops that require less water, making it impossible to confirm or deny the statement.

 

 

5. False

 

Reference:

 

From paragraph E: “During the day, sunlight activates the molecules, slowing down growth. If a plant finds itself in the shade, phytochromes are quickly inactivated – enabling it to grow faster to find sunlight again.”

 

Explanation

 Contrary to the statement, Paragraph E explains that plants grow faster in the shade because phytochromes are quickly inactivated, allowing them to seek sunlight for growth.


  

6. False

 

Reference:

 

From paragraph E: "Light-driven changes to phytochrome activity occur very fast, in less than a second,’ says Wigge. At night, however, it’s a different story. Instead of a rapid deactivation following sundown, the molecules gradually change from their active to inactive state."

 

Explanation

The passage clarifies that phytochromes undergo rapid changes in activity during the day but gradually change at night, indicating that they do not change state at the same speed day and night.

 

Questions and Answers 7-11
Do the following statements agree with the information given in Reading Passage 1? In boxes 7-11 on your answer sheet, write.

  • The Reading Passage has eight sections: A-H.
  • Which section contains the following information?
  • Write the correct letter, A-H, in boxes 7-11 on your answer sheet.

 

 

7. Mention of specialists who can make use of the research findings

8. a reference to a potential benefit of the research findings

9. scientific support for a traditional saying

10. a reference to people traditionally making plans based on plant behaviour

11. a reference to where the research has been reported

 

Plant Thermometer Trigger  Reading Answers with Explanations (7-11)

 

Type of question: Matching information

In this question type, you will be asked to match specific pieces of information, often dates, names, or events, from the reading passage with corresponding options provided in the question.

 

How to best answer: 
 

  • Read each statement carefully to understand the specific information being asked for.
  • Scan the passage for relevant dates or events in the reading passage that corresponds to each statement.
  • Eliminate incorrect options that do not match the information found in the passage.
  • Match the remaining options based on the information provided in the passage.
  • Verify your answers to ensure they match the information in the passage before finalising them.

 

7. H

 

Reference:

 

From paragraph H: "Cambridge is uniquely well-positioned to do this kind of research as we have outstanding collaborators nearby who work on more applied aspects of plant biology, and can help us transfer this new knowledge into the field."


 

Explanation

This reference indicates that specialists who can make use of the research findings are discussed, particularly highlighting the collaborative efforts with Cambridge and its partners to translate this knowledge into practical applications in the field of plant biology.


 

8. D

 

Reference:

 

From paragraph D: "Discovering the molecules that allow plants to sense temperature has the potential to accelerate the breeding of crops resilient to thermal stress and climate change."


 

Explanation

The passage suggests a significant benefit of the research findings, emphasising the potential to enhance crop resilience to climate change-induced thermal stress. This indicates a critical application of the discovered molecules in addressing the pressing issue of food security.
 

9. G

 

Reference:

 

From paragraph G: "In fact, the discovery of the dual role of phytochromes provides the science behind a well-known rhyme long used to predict the coming season: oak before ash we’ll have a splash, ash before oak we’re in for a soak."
 

Explanation

The scientific validation provided in this paragraph for a traditional saying adds credibility to the research findings. By linking scientific discoveries with long-held cultural observations, the passage underscores the relevance and practical implications of the study's outcomes.


 

10. C

 

Reference:

 

From paragraph C: "Farmers and gardeners have known for hundreds of years how responsive plants are to temperature: warm winters cause many trees and flowers to bud early, something humans have long used to predict weather and harvest times for the coming year."


 

Explanation

This section illustrates how the traditional knowledge of farmers and gardeners aligns with the scientific understanding presented in the passage. It emphasises the historical reliance on plant behaviour as a predictor for weather patterns and harvest times, showcasing the enduring relevance of this relationship.


 

11. A

 

Reference

From paragraph A: "The new findings, published in the journal Science, show that phytochromes control genetic switches in response to temperature as well as light to dictate plant development."


 

Explanation

The paragraph cited highlights the dissemination of the research findings, indicating their publication in a reputable scientific journal. This emphasises the credibility and significance of the discovery regarding phytochromes role in regulating plant development in response to environmental cues like temperature and light.


 

Questions and Answers 12-14
Answer the questions below.

  • Complete the sentences below.
  • Choose NO MORE THAN TWO WORDS from the passage for each answer.
  • Write your answers in boxes 12-14 on your answer sheet.

 

 

12. Daffodils are likely to flower early in response to _____________ weather.

13. If ash trees come into leaf before oak trees, the weather in ________________ will probably be wet.

14. The research was carried out using a particular species of ________________.


 

Plant Thermometer Trigger Reading Answers with Explanations (12-14)


 

Type of question: Sentence Completion

In this question type, you are required to fill in the blanks in a given sentence with words or phrases taken directly from the passage. These questions test your ability to understand specific details and information presented in the text.

 

How to answer: 

 

  • Read the sentence carefully to understand the context.
  • Identify keywords or clues that can help you find the answer in the passage.
  • Scan the passage for relevant information, focusing on the area around the blank.
  • Choose the answer that fits grammatically and contextually.
  • Verify your answers and finalise them.

 

 

12. Warm (Winter)

 

Reference:

 

From paragraph G: "Other species, such as daffodils, have considerable temperature sensitivity and can flower months in advance during a warm winter."

 

Explanation

Daffodils exhibit early flowering in response to warmer winters, showcasing their sensitivity to temperature changes, as highlighted in the passage.


 

13. Summer

 

Reference:

 

From paragraph G: "A warmer spring, and consequently a higher likeliness of a hot summer, will result in oak leafing before ash. A cold spring will see the opposite. As the British know only too well, a colder summer is likely to be a rain-soaked one."

 

Explanation

If ash trees leaf before oak trees, it indicates a warmer spring, suggesting a higher probability of a wetter summer, as described in the passage.


 

14. Mustard plant(s) / Mustard

 

Reference:

 

From paragraph H: "The work was done in a model system, using a mustard plant called Arabidopsis, but Wigge says the phytochrome genes necessary for temperature sensing are found in crop plants as well."


 

Explanation

The research was conducted utilising Arabidopsis, a type of mustard plant, implying that this species was instrumental in the study, as stated in the passage.
 

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FAQs

Q. How long is the IELTS Reading test?

Ans. The IELTS Reading test lasts for 60 minutes. This time includes reading the passages and answering all the questions. There is no extra time given for transferring answers to the answer sheet, so it is crucial to manage your time effectively. You need to pace yourself to ensure you have enough time to read each passage and answer the associated questions.

Q. Are the reading passages the same for the Academic and General Training versions?

Ans. No, the reading passages are different for each version. The Academic version includes texts taken from books, journals, magazines, and newspapers, which are more complex and written for a non-specialist audience. The General Training version includes extracts from everyday sources like notices, advertisements, company handbooks, and newspapers, focusing on basic survival English and practical information.

Q. How can I practise effectively for the IELTS Reading test?

Ans. Use official IELTS practice materials, read a variety of texts in English regularly, and take timed practice tests to become familiar with the test format and improve your reading skills and speed. Regular practice helps you build the stamina needed for the test and familiarise yourself with different question types and topics.