IELTS Forcast Reading Test 2025 - Q3 Test 1 with Practice Test, Answers And Explanation
Luyện tập đề IELTS Forcast Reading Test 2025 - Q3 Test 1 được lấy từ cuốn sách Forcast Test 2025 - Q3 với trải nghiệm thi IELTS trên máy và giải thích đáp án chi tiết bằng Linearthinking, kèm answer key và list từ vựng IELTS cần học trong bài đọc.
IELTS Forcast Reading Test 2025 - Q3 Test 1 with Practice Test, Answers And Explanation
Passage
❓ Câu hỏi passage 1
Question 1 - 4
Reading Passage has eight paragraphs A-H
Which paragraph contains the following information?
Write the correct letter, A-H
1
A list of food plants which need insects to make them productive
2
An explanation of why a genetic experiment may assist plant reproduction
3
A description of current research with advantages for the flower industry
4
An explanation of how insects perceive volatile compounds in plants
Question 5 - 9
Choose the correct letter, A, B, C or D.
Write the correct letter in boxes on your answer sheet.
5
According to the passage, spices were used in the past to
A
keep insects away from food.
B
improve the taste of food.
C
prevent the decay of food.
D
make food smell more attractive.
6
The Leonardoxa africana tree protects itself by
A
emitting a scent that repels plant-eating insects.
B
attracting and poisoning herbivorous insects.
C
chemically destroying the eggs of parasites.
D
attracting an enemy of herbivorous insects.
7
Which of the following statements about methyl salicylate is NOT true according to the passage?
A
It helps ants to protect their nests.
B
It helps herbivorous insects to find food.
C
It helps a rainforest tree to attract ants.
D
It helps a rainforest tree to avoid being eaten.
8
Which factor has made the problems of US fruit growers more serious?
A
Bees found an alternative source of food.
B
Chemicals were killing too many bees.
C
Fruit was decreasing in quality.
D
Bees have had their numbers reduced by disease.
9
Experiments in genetically manipulating the fragrance of ornamental flowers have
A
cost US$30 billion.
B
made the flowers more attractive to insects.
C
failed to produce a strong enough scent.
Question 10 - 13
Do the following statements agree with the information given in the Reading Passage?
TRUE if the statement agrees with the information
FALSE if the statement contradicts the information
NOT GIVEN if it is impossible to say what the writer thinks about this
10
The theory that plants defend themselves with smells is untested.
11
The smell from fruit-tree flowers is important to farmers.
12
The population of honeybees in Europe has declined.
13
Applying perfume to orchard trees is accepted as a good method of increasing pollination.
Passage
❓ Câu hỏi passage 2
Question 14 - 18
Reading Passage has six paragraphs A-F
Which paragraph contains the following information?
Write the correct letter, A-F
14
A description of an experiment involving both human and non-human cells of a specific type.
15
Possibilities for improved research into various serious medical conditions.
16
Contrasting views of the importance of the Petri dish.
17
A change remarked on by one scientist in the material used for the Petri dish.
18
A claim that the Petri dish enables a scientist to monitor the progress of an experiment on a regular basis.
Question 19 - 23
Look at the following statements and the list of people below.
Match each statement with the correct person, A-D.
Write the correct letter, A-D.
List of Findings
A
Alan Macfarlane
B
Professor Ludovic Vallier
C
Dr. Meritxell Huch
D
Dr. Madeline Lancaster
19
To deal with injury, cells must go through a series of activities in a particular order.
20
One technological development formed the basis of all modern scientific research.
21
A modification to the Petri dish allows experiments to provide more accurate information.
22
Petri dishes allow observation of medical conditions that are normally impossible to observe.
23
Visual evidence is a very important requirement for the provision of reliable information.
Question 24 - 26
Choose ONE WORD ONL Y from the passage for each answer.
Research in the MRC Lab of Molecular Biology
A team led by Dr. Madeline Lancaster is using special Petri dishes which prevent brain cells from to them. The aim is to allow the neurons to grow in three . This results in a that resembles a developing brain. The technology could help scientists study how neuron production varies in different species, leading to possibilities for increased medical knowledge.
Passage
❓ Câu hỏi passage 3
Question 27 - 31
Look at the following statements and the list of people below.
Match each statement with the correct person, A-F.
Write the correct letter, A-F.
List of Findings
A
Alfred North Whitehead
B
Ap Dijksterhuis
C
Timothy Wilson
D
Matthew Walker
E
Daniel Goleman
F
Howard Gardner
27
People find it easier to solve problems at a particular point in the sleep cycle.
28
People should change their general behaviour patterns in order to benefit more from the unconscious.
29
When solving problems, people should try to ignore negative thoughts.
30
People can come up with ideas which are more innovative if they temporarily put a problem aside.
31
People who make quick decisions are less likely to regret them.
Question 32 - 34
Complete the summary below.
Choose NO MORE THAN TWO WORDS from the passage for each answer.
Many scientists argue that people should make better use of their unconscious mind. Alfred North Whitehead, for example, gave support for the idea of - a term for people deliberately ignoring a problem over a period of time.
Experiments in Amsterdam that required students to consider a tricky situation found them making good decisions while carrying out an unconnected . Similarly, an experiment in Virginia which required subjects to make a selection from a number of different found people feeling happier with their decisions if they had made them quickly.
Question 35 - 40
Choose
TRUE if the statement agrees with the information
FALSE if the statement contradicts the information
NOT GIVEN if it is impossible to say what the writer thinks about this
35
Our unconscious mind helps us more than our conscious mind with complex problems.
36
Resting before going to sleep can result in improved solutions to problems.
37
Problems are more likely to be solved after dreamless sleep.
38
Matthew Walker's team assessed their subjects using a memory test.
39
Daydreams are more helpful to the unconscious than dreams which occur during sleep.
40
People often create their own barriers to problem-solving.
DOL IELTS Đình Lực
05/05/2026
📖 Bài đọc passage 1
Scented Plants
A
A. Many plants emit a smell. This may come from the flower of the plant, from the leaves, stem, or even, in some cases, from the root. What humans may perceive as a fragrant perfume is actually a tool used by plants to entice pollinators, discourage bacteria or fend off predators. Fragrances consist of small organic particles with high vapor pressures, so that a scent compound evaporates easily if exposed to the air; chemicals which evaporate in this way are described as volatile compounds.
B
Although we generally think of plant odors as pleasant, many volatile compounds in plants are toxic when eaten. These compounds are used by plants to protect themselves from bacterial attack. Humans have recognized and taken advantage of these plant-derived antibacterials since antiquity, when they were used to slow the spoilage of food. For example, the spice clove could be used in baked goods and prepared meats to slow the growth of mould and bacteria because a small amount was not dangerous to humans. Before the development of modern food preservation techniques, European civilization was heavily dependent on cloves and other tropical spices to ensure a long-lasting supply of food. However, the long distance from Europe to South-east Asia made these spices extremely expensive and was part of the motivation behind the search for a shorter route to Asia which resulted in the discovery of the Americas.
C
Although volatile compounds in plants probably originally evolved to repel herbivorous (plant-eating) animals of all kinds, they now perform a remarkable range of functions. An important one common to many plants is to attract animals which will spread that plant's pollen. Insects are the most common animals to interact with plants in this way, and most insects detect volatile compounds through the extremely sensitive antennae on their heads. Some antennae can detect an airborne volatile compound at concentrations of just a few parts per billion.
D
Other plants emit volatile compounds which function as toxins against invading insects, and still others emit such compounds when they have been injured, in order to deter insects from laying eggs on them and thus injuring them further. Volatile compounds released by plants in response to herbivore egg laying, for example, can attract parasites of the eggs, thereby preventing them from hatching. In this way the plant can avoid the attack of the hungry young herbivores that would have emerged from the eggs.
E
Volatile compounds in plants can also be used as a kind of currency in some very indirect defensive systems. In the rainforest tree Leonardoxa africana, for example, ants of the species Petalomyrmex phylax are attracted to young leaves because they emit high levels of the volatile compound methyl salicylate, a substance that ants need to use as an antiseptic in their nests; coincidentally, the ants attack any herbivorous insects that they encounter. It appears that methyl salicylate both attracts ants and rewards them for performing their valuable role in deterring herbivores. The web of interactions among plants and animals can become so complicated that it is difficult to detect what the outcome of the release of volatile compounds is. But it is clear that the system can have a defensive purpose, as many experiments have shown that the deactivation of a plant's volatile emission system makes it more vulnerable to herbivores.
F
Floral scent has a strong impact on the economic success of many agricultural crops that rely on insect pollinators, including fruit trees such as the bee-pollinated cherry, apple, apricot and peach, as well as vegetables and tropical plants such as the papaya. A decrease in fragrance emission, due to crossbreeding for fruit size or other characteristics, reduces the ability of plants to attract pollinators and may result in considerable losses for growers. This problem has been made worse in the United States by recent epidemics that have infected and killed many honeybees, the major insect pollinator.
G
Some plant breeders have tried to solve this pollination problem by spraying scent compounds on orchard trees to enhance honeybee foraging, but this approach was costly, and in the end proved to be inefficient. One of the reasons for its ineffectiveness was that general spraying of the crop could not tell insects exactly where the blossoms were. Clearly, a more refined strategy is needed; genetic manipulation of scents, for example, would allow growers to regulate the types of insect pollinators and the frequency of their visits.
H
Such manipulation of scent will also benefit people who grow flowers commercially. Cut flowers and potted plants play an important aesthetic part in human life. Unfortunately, traditional breeding has produced varieties with improved vase life, color and shape, while perfume has been sacrificed. The loss of scent among ornamental flowers, which have a worldwide annual value of more than US$30 billion, makes them important targets for the genetic manipulation of flower fragrance. Some preliminary experiments have already been carried out, but for technical reasons the scent was present in every part of the plant, rather than being localized in the flower, and the level of intensity of fragrance was below the threshold of detection for the human nose. The next generation of experiments, already in progress, will include more sophisticated schemes that target the expression of scent specifically to flowers or other organs, such as special glands that can store antibacterial or herbivore-repellent compounds.
🔥 Đáp án & giải thích 1
1
F
Giải thích chi tiết
☺️ Ứng dụng Linearthinking để giải quyết dạng bài Matching Information
📌 Dạng Matching Information chúng ta nên làm cuối cùng, sau khi đã làm các dạng câu hỏi khác nhé DOLBIES, bởi vì lúc này mình đã đọc và hiểu nội dung của bài rồi, cộng thêm nghệ thuật Specify của Linearthinking → sẽ nhanh chóng tìm được vị trí đáp án hơn!!
-------
Step 01: Read the question to predict
Hiểu câu hỏi: A list of food plants which need insects to make them productive
Specify & Predict: Đoạn văn này sẽ liệt kê các loại cây trồng cụ thể (ví dụ: cây ăn quả, rau, cây nhiệt đới...) và nêu rõ chúng phụ thuộc vào côn trùng thụ phấn.
-------
Step 02: Khoanh vùng đoạn văn
🔍 Từ khóa: “list", "food plants", "insects", "productive"
-> Dựa vào các từ khoá trên, có thể khoanh vùng được đoạn F vì có một danh sách liệt kê: "agricultural crops that rely on insect pollinators" (cây nông nghiệp phụ thuộc vào côn trùng thụ phấn = food plants need insects); bao gồm "fruit trees" (cây ăn quả) như "cherry, apple, apricot and peach" (anh đào, táo, mơ, đào) và "vegetables" (rau củ) như "papaya" (đu đủ).
-> Đây là ví dụ cụ thể cho "A list of food plants which need insects to make them productive".
A simple piece of scientific equipment is helping research in three institutions in Cambridge, UK
A
A. Petri dishes, invented by German microbiologist Julius Richard Petri in 1887, rarely receive the appreciation or attention that their more complex lab companions like the microscope enjoy. They are simple, utilitarian little things, and it's understandable that some people see them as just shallow dishes with lids. But Petri dishes deserve celebrating: they are still at the forefront of scientific discovery.
B
B. The invention of the Petri dish, and the advances it has helped to create, are part of a bigger whole, of course - the development of glass scientific instruments, from microscope lenses to laboratory beakers. In The Glass Bathyscaphe: How Glass Changed the World, Alan Macfarlane argues that without glass, the Renaissance and the scientific revolution would never have happened. Around 70 percent of what we know about the world comes in through our eyes, Macfarlane points out, and glass instruments enabled us to see better. Until about 1400, knowledge was based on what people had been told in the past. "Glass allowed the growth of the experimental method. Don't trust what you are being told: see it for yourself. It was transformational," he says.
C
At the Wellcome-MRC Cambridge Stem Cell Institute, Professor Ludovic Vallier says that his first encounter with a Petri dish was a classic example of understanding the world in this way: students used the dishes to see which bacteria could grow in the presence of antibiotics. "It's good to see things grow," he says. "It was a fascinating experience. Now, we grow cells in the Petri dish, and we don't use glass any more, but plastic." Today, his team focuses on stem cells, which have the capacity to become any cell type in the human body: neurons, skin cells, liver cells, and so on. Vallier and his colleagues study them in order to understand how they do this, and how they can produce more cells. And to study them, they need to grow them. "We put the stem cells on the dish and then we feed them and they grow," he says. "And then we divide them and distribute them in new Petri dishes, and we grow them again. We feed them on a liquid medium that is basically food for cells; it tells them to grow and also what to do, as we want to produce new cells. So by feeding them this medium we can allow the cells to become neurons, cardiac cells, liver cells, and so on. We can then model disease in a lab."
D
'Disease in a dish' is also the focus of Dr. Meritxell Huch's team at the Gurdon Institute. They use between 50 and 150 Petri dishes every day to grow mouse liver and human liver cells in order to study how the liver can regenerate itself. Huch's team is examining the molecular mechanisms by which these cells decide to multiply. She says: "You can divide regeneration into different phases. The cells first have to realize that there is damage and activate the response. Once they activate the response, the cells will proliferate to compensate for the loss of cells owing to the damage. And once they have proliferated, they then have to become functional cells."
E
In the MRC Laboratory of Molecular Biology, Dr. Madeline Lancaster and her team grow 'mini-brains' in hundreds of Petri dishes. Here, the dish has been specially treated to stop cells from sticking to it and to encourage them to float freely. Dr. Lancaster explains that they want the cells to develop in three, rather than two, dimensions as that's the way our brains are. "If you can grow neurons on a dish in two dimensions, you can see individual neurons and see what they do, but you won't be able to understand the architecture of those cells—their positioning relative to one another." She says that this new method gives you a structure that looks a lot more like that of an actual developing brain.
F
The aim of this research is to look at exactly how neurons are made and how that differs in humans compared with other species. One day, says Lancaster, this work could translate into understanding far more about Alzheimer's disease, Parkinson's, and schizophrenia. So, in a world of cutting-edge and highly complex technology, Petri dishes, in their relative simplicity, remain a vital weapon in the fight against the world's most difficult diseases. And they also enable a hands-on approach that she finds satisfying. "It's a bit like gardening," she says. "You're taking care of this thing. You keep an eye on it and you check it every day. You change the media this day or that day to help it grow better. It's rewarding to see something grow before your eyes. There's something about the interplay between new, next-generation, and classic technologies. They give you capabilities that were just not possible before."
🔥 Đáp án & giải thích 2
14
D
Giải thích chi tiết
☺️ Ứng dụng Linearthinking để giải quyết dạng bài Matching Information
📌 Dạng Matching Information chúng ta nên làm cuối cùng, sau khi đã làm các dạng câu hỏi khác nhé DOLBIES, bởi vì lúc này mình đã đọc và hiểu nội dung của bài rồi, cộng thêm nghệ thuật Specify của Linearthinking → sẽ nhanh chóng tìm được vị trí đáp án hơn!!
-------
Step 01: Read the question to predict
Hiểu câu hỏi: A description of an experiment involving both human and non-human cells of a specific type
Specify & Predict: Đoạn văn này sẽ mô tả một hoạt động nghiên cứu cụ thể, nơi người ta nuôi cấy đồng thời tế bào của người và một loài khác (như chuột chẳng hạn) để nghiên cứu một bộ phận nào đó.
-------
Step 02: Khoanh vùng đoạn văn
🔍 Từ khóa: “description", "experiment", "human and non-human cells"
-> Dựa vào các từ khoá trên, có thể khoanh vùng được đoạn D vì nó mô tả rất chi tiết công việc của nhóm nghiên cứu: "mouse liver and human liver cells" (tế bào gan chuột và gan người - đáp ứng human and non-human cells of a specific type); nghiên cứu cách "liver can regenerate itself" (gan tự tái tạo - mô tả thí nghiệm).
-> Đây là miêu tả cụ thể cho "an experiment involving both human and non-human cells of a specific type".
Great scientists and artists have long known about the unconscious mind. The founder of psychoanalysis, Sigmund Freud, argued that most of our real motivation lies below conscious awareness and that we require the services of a psychoanalyst to explain ourselves to ourselves. Even those celebrated scientists who believe that Freud exaggerated the importance of the unconscious argue that it is a part of the in our minds which we should learn to control and take advantage of.
The great mathematician Alfred North Whitehead seemed to be a supporter of unconscious mental processing when he said: 'It is a profoundly erroneous truism, repeated by all copybooks and by eminent people making speeches, that we should cultivate the habit of thinking about what we are doing. The precise opposite is the case.' What Whitehead meant by this is that some of the greatest breakthroughs in creativity occur when a problem is consciously shelved for a while - 'don't think about it, just sleep on it' - after which the unconscious mind offers a solution. This is a process which psychoanalysts call 'incubation'.
Now the latest psychological research confirms that we can all incubate a problem to our own advantage. Ap Dijksterhuis, a psychologist at the University of Amsterdam, has recently published a series of experiments in which students were presented with complex everyday problems to solve. In one experiment they were given the opportunity to think carefully about a decision; in another experiment they were distracted by an irrelevant task whilst making a decision. The surprising result, published in the Journal of Personality and Social Psychology, was that 'unconscious' minds made the better decisions.
Timothy Wilson and colleagues from the University of Virginia's psychology department conducted another experiment. Participants were presented with five posters and asked to choose one to take home. A little later, they were telephoned and asked how satisfied they were with their choice - a measure of whether they had made the right decision from a subjective point of view. Some participants had picked their poster straight away, whereas others were asked to analyse carefully the pros and cons of each poster. It turned out that people who had analysed were less satisfied with their choice than people who had not applied logic. Paradoxically, it seems that those who had consciously weighed up the various attributes had made relatively poor decisions.
The conclusion that has to be drawn from current research suggests the somewhat counterintuitive idea that the more complex a problem is, the less likely it becomes that conscious thought can contribute much. If a dilemma is particularly difficult, a lot of information has to be taken into account and it appears that conscious thought is not good at this. The message is that when it comes to intricate problems with many variables, you should let the unconscious deal with it.
Using dreaming is one way of doing this. Dreams are the part of sleep most strongly correlated with rapid eye movement (REM) and have been associated with enhanced creativity and novel solutions. The latest research suggests that, if you want to enhance unconscious problem-solving, you should try to think about your problems immediately after dreaming. In a recent experiment, psychiatrist Matthew Walker and colleagues from the Laboratory of Neurophysiology at Harvard Medical School woke up half of their experimental subjects immediately after REM sleep, and the other half just after sleep with no dreams, and then asked them to solve crossword puzzles. REM awakenings provided a 32 per cent advantage in the number of puzzles solved, compared with non-REM awakenings.
But you don't have to be asleep to use the unconscious mind when you are not thinking of anything in particular, which is why daydreams are so useful in the quest for creativity. Daniel Goleman, the famous psychologist who proposed the theory of emotional intelligence', urges us to be more aware of, and discount, a key obstacle that the conscious mind imposes on the unconscious: that of self-censorship. This is the voice that whispers to you, 'they'll think I'm foolish' or 'that will never work', keeping you imprisoned within the boundaries of what is deemed acceptable. Howard Gardner, a professor of cognition and education at Harvard University, suggests that we free ourselves from the straitjacket of always doing things the same way. In seeking to go beyond the routine and conventional, you will gain confidence in trusting your unconscious, he says.
🔥 Đáp án & giải thích 3
27
D
Giải thích chi tiết
☺️ Ứng dụng Linearthinking để giải quyết dạng bài Matching Names
Step 01: Read the question to understand main idea
Simplified: People find it easier to solve problems at a particular point in the sleep cycle
-------
Step 02: Locate relevant information
🔍 Từ khoá: solve problems, sleep cycle, easier
=> Dựa vào các từ khoá trên -> Tìm được trích dẫn ở đoạn kế cuối.
-------
Step 03: Read relevant information to understand (main + detail)
📌 Trích dẫn:"psychiatrist Matthew Walker and colleagues from the Laboratory of Neurophysiology at Harvard Medical School woke up half of their experimental subjects immediately after REM sleep, and the other half just after sleep with no dreams, and then asked them to solve crossword puzzles. REM awakenings provided a 32 per cent advantage in the number of puzzles solved, compared with non-REM awakenings."
Simplified: Matthew Walker and colleagues woke up subjects after REM sleep vs non-REM sleep . REM awakenings provided a 32% advantage in solving puzzles
Main idea: Thí nghiệm → đánh thức ngay sau REM sleep = tăng 32% khả năng giải crossword puzzles → REM sleep giúp giải quyết vấn đề tốt hơn.
-------
Step 04: Compare meaning with meaning
Nội dung tìm được trong bài: REM sleep → giúp con người giải quyết vấn đề tốt hơn (32% advantage).
Nội dung câu hỏi: Con người → giải quyết vấn đề dễ hơn tại một giai đoạn cụ thể trong chu kỳ giấc ngủ.
B. Although we generally think of plant odors as pleasant, many volatile compounds in plants are toxic when eaten. These compounds are used by plants to protect themselves from bacterial attack. Humans have recognized and taken advantage of these plant-derived antibacterials since antiquity, when they were used to slow the spoilage of food. For example, the spice clove could be used in baked goods and prepared meats to slow the growth of mould and bacteria because a small amount was not dangerous to humans. Before the development of modern food preservation techniques, European civilization was heavily dependent on cloves and other tropical spices to ensure a long-lasting supply of food. However, the long distance from Europe to South-east Asia made these spices extremely expensive and was part of the motivation behind the search for a shorter route to Asia which resulted in the discovery of the Americas.
C. Although volatile compounds in plants probably originally evolved to repel herbivorous (plant-eating) animals of all kinds, they now perform a remarkable range of functions. An important one common to many plants is to attract animals which will spread that plant's pollen. Insects are the most common animals to interact with plants in this way, and most insects detect volatile compounds through the extremely sensitive antennae on their heads. Some antennae can detect an airborne volatile compound at concentrations of just a few parts per billion.
D. Other plants emit volatile compounds which function as toxins against invading insects, and still others emit such compounds when they have been injured, in order to deter insects from laying eggs on them and thus injuring them further. Volatile compounds released by plants in response to herbivore egg laying, for example, can attract parasites of the eggs, thereby preventing them from hatching. In this way the plant can avoid the attack of the hungry young herbivores that would have emerged from the eggs.
E. Volatile compounds in plants can also be used as a kind of currency in some very indirect defensive systems. In the rainforest tree Leonardoxa africana, for example, ants of the species Petalomyrmex phylax are attracted to young leaves because they emit high levels of the volatile compound methyl salicylate, a substance that ants need to use as an antiseptic in their nests; coincidentally, the ants attack any herbivorous insects that they encounter. It appears that methyl salicylate both attracts ants and rewards them for performing their valuable role in deterring herbivores. The web of interactions among plants and animals can become so complicated that it is difficult to detect what the outcome of the release of volatile compounds is. But it is clear that the system can have a defensive purpose, as many experiments have shown that the deactivation of a plant's volatile emission system makes it more vulnerable to herbivores.
F. Floral scent has a strong impact on the economic success of many agricultural crops that rely on insect pollinators, including fruit trees such as the bee-pollinated cherry, apple, apricot and peach, as well as vegetables and tropical plants such as the papaya. A decrease in fragrance emission, due to crossbreeding for fruit size or other characteristics, reduces the ability of plants to attract pollinators and may result in considerable losses for growers. This problem has been made worse in the United States by recent epidemics that have infected and killed many honeybees, the major insect pollinator.
G. Some plant breeders have tried to solve this pollination problem by spraying scent compounds on orchard trees to enhance honeybee foraging, but this approach was costly, and in the end proved to be inefficient. One of the reasons for its ineffectiveness was that general spraying of the crop could not tell insects exactly where the blossoms were. Clearly, a more refined strategy is needed; genetic manipulation of scents, for example, would allow growers to regulate the types of insect pollinators and the frequency of their visits.
H. Such manipulation of scent will also benefit people who grow flowers commercially. Cut flowers and potted plants play an important aesthetic part in human life. Unfortunately, traditional breeding has produced varieties with improved vase life, color and shape, while perfume has been sacrificed. The loss of scent among ornamental flowers, which have a worldwide annual value of more than US$30 billion, makes them important targets for the genetic manipulation of flower fragrance. Some preliminary experiments have already been carried out, but for technical reasons the scent was present in every part of the plant, rather than being localized in the flower, and the level of intensity of fragrance was below the threshold of detection for the human nose. The next generation of experiments, already in progress, will include more sophisticated schemes that target the expression of scent specifically to flowers or other organs, such as special glands that can store antibacterial or herbivore-repellent compounds.
C. At the Wellcome-MRC Cambridge Stem Cell Institute, Professor Ludovic Vallier says that his first encounter with a Petri dish was a classic example of understanding the world in this way: students used the dishes to see which bacteria could grow in the presence of antibiotics. "It's good to see things grow," he says. "It was a fascinating experience. Now, we grow cells in the Petri dish, and we don't use glass any more, but plastic." Today, his team focuses on stem cells, which have the capacity to become any cell type in the human body: neurons, skin cells, liver cells, and so on. Vallier and his colleagues study them in order to understand how they do this, and how they can produce more cells. And to study them, they need to grow them. "We put the stem cells on the dish and then we feed them and they grow," he says. "And then we divide them and distribute them in new Petri dishes, and we grow them again. We feed them on a liquid medium that is basically food for cells; it tells them to grow and also what to do, as we want to produce new cells. So by feeding them this medium we can allow the cells to become neurons, cardiac cells, liver cells, and so on. We can then model disease in a lab."
D. 'Disease in a dish' is also the focus of Dr. Meritxell Huch's team at the Gurdon Institute. They use between 50 and 150 Petri dishes every day to grow mouse liver and human liver cells in order to study how the liver can regenerate itself. Huch's team is examining the molecular mechanisms by which these cells decide to multiply. She says: "You can divide regeneration into different phases. The cells first have to realize that there is damage and activate the response. Once they activate the response, the cells will proliferate to compensate for the loss of cells owing to the damage. And once they have proliferated, they then have to become functional cells."
E. In the MRC Laboratory of Molecular Biology, Dr. Madeline Lancaster and her team grow 'mini-brains' in hundreds of Petri dishes. Here, the dish has been specially treated to stop cells from sticking to it and to encourage them to float freely. Dr. Lancaster explains that they want the cells to develop in three, rather than two, dimensions as that's the way our brains are. "If you can grow neurons on a dish in two dimensions, you can see individual neurons and see what they do, but you won't be able to understand the architecture of those cells—their positioning relative to one another." She says that this new method gives you a structure that looks a lot more like that of an actual developing brain.
F. The aim of this research is to look at exactly how neurons are made and how that differs in humans compared with other species. One day, says Lancaster, this work could translate into understanding far more about Alzheimer's disease, Parkinson's, and schizophrenia. So, in a world of cutting-edge and highly complex technology, Petri dishes, in their relative simplicity, remain a vital weapon in the fight against the world's most difficult diseases. And they also enable a hands-on approach that she finds satisfying. "It's a bit like gardening," she says. "You're taking care of this thing. You keep an eye on it and you check it every day. You change the media this day or that day to help it grow better. It's rewarding to see something grow before your eyes. There's something about the interplay between new, next-generation, and classic technologies. They give you capabilities that were just not possible before."
Great scientists and artists have long known about the unconscious mind. The founder of psychoanalysis, Sigmund Freud, argued that most of our real motivation lies below conscious awareness and that we require the services of a psychoanalyst to explain ourselves to ourselves. Even those celebrated scientists who believe that Freud exaggerated the importance of the unconscious argue that it is a part of the in our minds which we should learn to control and take advantage of.
The great mathematician Alfred North Whitehead seemed to be a supporter of unconscious mental processing when he said: 'It is a profoundly erroneous truism, repeated by all copybooks and by eminent people making speeches, that we should cultivate the habit of thinking about what we are doing. The precise opposite is the case.' What Whitehead meant by this is that some of the greatest breakthroughs in creativity occur when a problem is consciously shelved for a while - 'don't think about it, just sleep on it' - after which the unconscious mind offers a solution. This is a process which psychoanalysts call 'incubation'.
Now the latest psychological research confirms that we can all incubate a problem to our own advantage. Ap Dijksterhuis, a psychologist at the University of Amsterdam, has recently published a series of experiments in which students were presented with complex everyday problems to solve. In one experiment they were given the opportunity to think carefully about a decision; in another experiment they were distracted by an irrelevant task whilst making a decision. The surprising result, published in the Journal of Personality and Social Psychology, was that 'unconscious' minds made the better decisions.
Timothy Wilson and colleagues from the University of Virginia's psychology department conducted another experiment. Participants were presented with five posters and asked to choose one to take home. A little later, they were telephoned and asked how satisfied they were with their choice - a measure of whether they had made the right decision from a subjective point of view. Some participants had picked their poster straight away, whereas others were asked to analyse carefully the pros and cons of each poster. It turned out that people who had analysed were less satisfied with their choice than people who had not applied logic. Paradoxically, it seems that those who had consciously weighed up the various attributes had made relatively poor decisions.
The conclusion that has to be drawn from current research suggests the somewhat counterintuitive idea that the more complex a problem is, the less likely it becomes that conscious thought can contribute much. If a dilemma is particularly difficult, a lot of information has to be taken into account and it appears that conscious thought is not good at this. The message is that when it comes to intricate problems with many variables, you should let the unconscious deal with it.
Using dreaming is one way of doing this. Dreams are the part of sleep most strongly correlated with rapid eye movement (REM) and have been associated with enhanced creativity and novel solutions. The latest research suggests that, if you want to enhance unconscious problem-solving, you should try to think about your problems immediately after dreaming. In a recent experiment, psychiatrist Matthew Walker and colleagues from the Laboratory of Neurophysiology at Harvard Medical School woke up half of their experimental subjects immediately after REM sleep, and the other half just after sleep with no dreams, and then asked them to solve crossword puzzles. REM awakenings provided a 32 per cent advantage in the number of puzzles solved, compared with non-REM awakenings.
But you don't have to be asleep to use the unconscious mind when you are not thinking of anything in particular, which is why daydreams are so useful in the quest for creativity. Daniel Goleman, the famous psychologist who proposed the theory of emotional intelligence', urges us to be more aware of, and discount, a key obstacle that the conscious mind imposes on the unconscious: that of self-censorship. This is the voice that whispers to you, 'they'll think I'm foolish' or 'that will never work', keeping you imprisoned within the boundaries of what is deemed acceptable. Howard Gardner, a professor of cognition and education at Harvard University, suggests that we free ourselves from the straitjacket of always doing things the same way. In seeking to go beyond the routine and conventional, you will gain confidence in trusting your unconscious, he says.
