Plant ‘thermometer’ triggers springtime growth by measuring night-time heat: reading answers and analysis

Were other scientists surprised by the Cambridge discovery?

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.

Why: A reports the discovery and where it was published, but says nothing about how other scientists reacted. No surprise, no reaction at all, so NOT GIVEN.

The trap: 'Researchers have revealed' and 'actually change their function' make the finding sound surprising. That's the writer's tone, not a report of other scientists' reaction.

Might the 2050 farming target not be reached?

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

Why: If something is a 'major threat to achieving' a target, the target might not be met. 'Could be missed' says the same thing. TRUE.

The trap: Some students hesitate because the passage doesn't say the target will be missed. The statement only says 'could', and a threat is exactly that.

Are wheat and rice harmed by rising temperatures?

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

Why: 'Sensitive to high temperatures' means they're harmed by heat, and the next sentence puts a number on it: about 10% less yield per degree. TRUE.

Could the research lead to crops that need less water?

could help us breed tougher crops… has the potential to accelerate the breeding of crops resilient to thermal stress and climate change

Why: The crops the passage imagines are tougher against heat ('thermal stress') and climate change. Water isn't mentioned anywhere, so you can't confirm or deny it. NOT GIVEN.

The trap: 'Climate change' and 'tougher crops' make drought resistance feel like part of the deal. Heat resistance and water use are different things, and the passage only talks about heat.

Do plants grow faster in sunlight than in shade?

During the day, sunlight activates the molecules, slowing down growth. If a plant finds itself in shade, phytochromes are quickly inactivated - enabling it to grow faster to find sunlight again.

Why: Sunlight slows growth, and shade lets a plant grow faster. The statement says the opposite, so FALSE.

The trap: Common sense says plants need sun to grow, which pushes people to TRUE. This test is about the passage, and it clearly reverses that: plants in shade speed up to reach the light.

Do phytochromes change state equally fast by day and by night?

Light-driven changes to phytochrome activity occur very fast, in less than a second… At night, however, it's a different story… the molecules gradually change from their active to inactive state.

Why: By day the change takes less than a second. At night it happens 'gradually', and the writer even says 'it's a different story'. The speeds differ, so FALSE.

The trap: Section B says the night-time change is 'directly proportional to temperature', which can make it sound fast on warm nights. It's still a gradual process, not the sub-second switch of daytime.

Also accepted: warm winter

What kind of weather makes daffodils flower early?

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

Why: The gap is an adjective before 'weather', and the passage says 'a warm winter'. 'Warm' is enough; 'warm winter' is also accepted, as it's within two words.

The trap: 'Temperature' is the noun people grab from the same sentence, but 'temperature weather' doesn't work. Writing 'winter' alone loses the key idea that it's warmth that triggers flowering.

If ash leafs before oak, which season will probably be wet?

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.

Why: Follow the chain: warm spring means oak first, so a cold spring means ash first ('the opposite'). A cold spring is followed by a colder summer, and that's 'likely to be a rain-soaked one'. Summer.

The trap: 'Spring' is the season mentioned with the leafing order, so many people write it. But spring is what causes ash to leaf first; the wet weather comes in summer.

Also accepted: mustard plants / mustard

Which plant species was the research done on?

The work was done in a model system, using a mustard plant called Arabidopsis

Why: 'A particular species of ___' needs a type of plant, and the passage says 'a mustard plant'. 'Mustard plant', 'mustard plants' or just 'mustard' are all accepted.

The trap: 'Arabidopsis' is the name of the species itself, so 'a species of Arabidopsis' doesn't match the sentence. 'Crop plants' appears later but is where the genes are also found, not what was used.