Reading Passage 1
Plant Survival in Extreme Environments
Plants are often imagined as passive organisms, but many species survive in environments that appear almost impossible for life. In deserts, high mountains and salty coastal areas, plants must cope with limited water, intense sunlight, poor soil and sudden temperature changes. Their survival depends on adaptations that reduce loss, increase storage and protect delicate tissues.
One of the most important problems is drought. Many plants lose water through tiny openings in their leaves called stomata. Some desert plants open these openings mainly at night, when temperatures are lower and evaporation is reduced. This allows them to take in carbon dioxide while limiting water loss during the hottest part of the day.
Leaf structure is also important. Thick or waxy leaves can reduce evaporation, while very small leaves expose less surface area to the air. In some species, leaves have become spines, leaving the stem to carry out photosynthesis. A protective outer membrane can also prevent water escaping from plant tissues.
Roots provide another strategy. Some plants produce extremely deep roots that reach underground water, while others spread shallow roots over a wide area to absorb brief rainfall quickly. Several desert species store water in underground organs or swollen stems, allowing them to survive long dry periods.
Plants must also defend themselves. In harsh environments, replacing damaged tissue is costly, so many species use chemical defences to discourage pests and grazing animals. Such adaptations show that plant survival is not based on a single solution but on a combination of structures and behaviours.
Reading Passage 2
The Changing Purpose of Maps
A. Maps are often treated as neutral pictures of the world, but they have always involved choices. A mapmaker decides what to include, what to leave out and what to emphasise. For this reason, maps can reveal as much about human priorities as about geography.
B. Early maps were shaped by belief, trade and politics. Some placed religious centres at the middle of the world; others exaggerated the size of powerful territories. Accuracy mattered, but it was not the only purpose. A map could also express identity, ambition or authority.
C. During the age of empire, maps became closely connected with political power. Drawing borders, naming regions and measuring land were ways of claiming control. Local names and traditional understandings of territory were often replaced by official labels.
D. Digital mapping has transformed the field again. Online maps combine satellite images, traffic information, business listings and user location data. Instead of being fixed objects, maps now change constantly according to time, movement and individual preference.
E. This personalisation is convenient, but it raises questions. When a map recommends one route, restaurant or neighbourhood over another, it may influence choices without users noticing. Commercial interests can therefore become hidden inside simple navigation.
F. Maps can also be powerful tools in emergencies. After floods or earthquakes, crisis maps built from reports, satellite images and volunteer updates can show blocked roads, damaged buildings and urgent needs. These maps help organisations decide where to send resources first.
G. The history of mapping shows that maps do more than represent space. They organise knowledge, guide movement and shape decisions. Whether drawn on paper or generated by algorithms, maps are active tools in social life.
Reading Passage 3
Fermentation: An Ancient Technology Reconsidered
Fermentation is one of humanity’s oldest food technologies. It occurs when microbes such as bacteria, yeasts or moulds change the chemistry of food. The process can produce bread, yoghurt, cheese, soy sauce, kimchi and many other foods central to different cuisines.
Historically, fermentation was valuable because it helped preserve food before refrigeration existed. By increasing acidity, producing alcohol or encouraging beneficial microbes, fermentation made it harder for harmful organisms to grow. This allowed communities to store seasonal produce and survive periods when fresh food was limited.
Fermentation also transformed flavour. Many fermented foods have strong, complex tastes that cannot be created simply by adding salt or sugar. The process may produce sourness, sweetness, bitterness or savoury depth. It can also change texture, making food softer, lighter or easier to digest.
With modern refrigeration and industrial food production, some traditional fermentation practices declined. Packaged foods offered consistency and convenience, while home fermentation came to seem old-fashioned or risky. In many places, knowledge that had once been passed through families became less common.
Recently, however, fermentation has attracted renewed attention. Chefs value it for flavour, scientists study it for its effects on microbes in the human body, and environmental thinkers see it as a way to reduce food waste. The return of fermentation shows that an ancient technique can remain relevant when people reconsider the relationship between food, health and culture.
