Carnivorous plant
Read Carnivorous plant and check the IELTS Reading answers. The naturalist and author of Origin of Species, Charles Darwin, was fascinated by carnivorous plants. In 1860, soon after he came across his first carnivorous plant — the sundew, Drosera — he wrote, 'I care more about Drosera than the orig…
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The naturalist and author of Origin of Species, Charles Darwin, was fascinated by carnivorous plants. In 1860, soon after he came across his first carnivorous plant — the sundew, Drosera — he wrote, 'I care more about Drosera than the origin of all the species in the world.' He spent months running experiments on the plants. He dropped flies and bits of meat on their leaves and watched them slowly fold their sticky tentacles over their prey. He thought it incredible that brushing a leaf with a single strand of human hair was enough to bring about a response. Yet sundews, he observed, ignored raindrops. To react to such a false alarm, he reasoned, would obviously be a great evil to the plant. This was no accident. This was adaptation.
Vocabulary from this passage
30 words worth learning before you sit the test, each with the sentence it appears in.
- accumulation noun
The acquisition or gradual gathering of something; a mass or quantity that has built up
The accumulation of toxic chemicals poses a significant risk to modern ecosystems.
- benign adjective
Gentle, kind, or (of a climate/environment) mild and favorable; not harmful
The region offered a benign habitat with mild winters and abundant resources.
- contingent adjective
Occurring or existing only if (certain circumstances) are the case; dependent on
The collapse of a society is often contingent on a complex interplay of local factors.
- conventional adjective
Based on or in accordance with what is generally done, believed, or widely accepted
Carnivorous plants have an advantage over conventional plants in nutrient-poor soil conditions.
- convex adjective
Having an outline or surface that curves outward like the exterior of a circle or sphere
The leaf rapidly changes shape from convex to concave to trap the unsuspecting insect.
- eclipse verb
To deprive someone or something of significance or power; to obscure or overshadow
Some believe environmental problems now eclipse all other global threats in importance.
- enigma noun
A person, thing, or situation that is mysterious, puzzling, or difficult to understand
The sudden disappearance of the civilization remains an enigma to modern historians.
- environmental degradation noun
The deterioration of the environment through depletion of resources such as air, water, and soil
Patterns of environmental degradation often preceded the fall of historical societies.
- evolutionary adjective
Relating to the gradual development of living organisms from earlier forms during the history of the earth
Scientists are studying the evolutionary forces that drove these plants to consume meat.
- hypothesise verb
To put something forward as a hypothesis; to suggest a theory based on limited evidence
Archaeologists hypothesise that the arrangement of stones indicates the use of tents.
- inconceivable adjective
Not capable of being imagined or grasped mentally; unbelievable
Survival in sub-arctic conditions is inconceivable without the ability to control fire.
- interlocking adjective
Connecting or fitting together so that the individual parts affect each other or hold together
The interlocking spines prevent the prey from escaping once the trap has snapped shut.
- maritime adjective
Connected with the sea, especially in relation to seafaring commercial or military activity
The area enjoyed a maritime climate, which moderated the temperature extremes.
- painstakingly adverb
With great care and thoroughness
The ancient structures had been painstakingly constructed over many generations.
- photosynthesis noun
The process by which green plants use sunlight to synthesize nutrients from carbon dioxide and water
Pitcher plants are inefficient at photosynthesis due to the shape of their leaves.
- preservation noun
The action of maintaining something in its original or existing state
Caves aid the preservation of archaeological material better than open-air sites.
- reason verb
To form conclusions, judgments, or inferences from facts or premises
Darwin reasoned that the plant ignored rain to avoid wasting energy on a false alarm.
- refuge noun
A condition of being safe or sheltered from pursuit, danger, or trouble
Caves offered refuge from the severe flooding that occurred in the valley below.
- reminiscent adjective
Tending to remind one of something; suggesting a comparison or resemblance
The ruins were reminiscent of the great monuments described in ancient literature.
- resilience noun
The capacity to recover quickly from difficulties; toughness and ability to adapt
The sudden disappearance of these cultures challenges our understanding of human resilience.
- secrete verb
To produce and discharge a substance, especially from the cells or glands of a living organism
Certain plants secrete sticky fluids to trap insects which are then digested for nutrients.
- sedimentation noun
The process of settling or being deposited as a sediment
The sedimentation of lakes helped preserve archaeological remains for thousands of years.
- sophisticated adjective
Developed to a high degree of complexity; showing advanced organization or technique
The mechanism by which the plant captures prey is surprisingly sophisticated for a non-sentient organism.
- stimulate verb
To raise levels of physiological or nervous activity in the body or a biological system
A single touch is not enough to stimulate the trap to close; a second contact is required.
- substantiate verb
To provide evidence to support or prove the truth of a statement or claim
Recent archaeological discoveries substantiate the theory that environmental damage caused the collapse.
- suppression noun
The action of forcibly preventing, inhibiting, or putting an end to a process or activity
The suppression of natural wildfires has inadvertently allowed competitor species to overtake the habitat.
- testify verb
To serve as evidence or proof of something's existence or truth
The presence of ash testifies to the early use of fire by Neanderthals.
- trajectory noun
The path followed by a projectile or object; a curve or surface describing a development path
It is inaccurate to assume all societies follow the same trajectory from birth to decline.
- vantage point noun
A place or position affording a good view of something
The caves located high above the valley provided an excellent vantage point for watching game.
- vigorously adverb
In a way that involves physical strength, effort, or energy; forcefully
The severity of climate change predictions is vigorously debated within the scientific community.
Answers with explanations
- 1. raindrops
The text explains that Darwin observed how the plant reacted to different stimuli. It specifically states that the plant **ignored raindrops** to avoid 'false alarms'. The answer matches the question asking what the plant did not respond to.
- 2. stomach
The question asks what the closed leaves act like for a short period. The text states that after snapping shut, the leaf **formed itself into a temporary ‘stomach’** to digest the prey. The word 'stomach' fits the gap.
- 2-3: A
2: The question asks what the closed leaves act like for a short period. The text states that after snapping shut, the leaf **formed itself into a temporary ‘stomach’** to digest the prey. The word 'stomach' fits the gap.
3: The text describes the process where the electric charge travels down tunnels and **opens up pores** in the cell membranes. The word 'pores' completes the sentence regarding what opens in the cell walls (membranes).
- 3. pores
The text describes the process where the electric charge travels down tunnels and **opens up pores** in the cell membranes. The word 'pores' completes the sentence regarding what opens in the cell walls (membranes).
- 3-4: C
3: The text describes the process where the electric charge travels down tunnels and **opens up pores** in the cell membranes. The word 'pores' completes the sentence regarding what opens in the cell walls (membranes).
4: The text describes the mechanism of the Bladderwort. After the trap shuts, the cells **pump water out** to reset the trap, which results in **creating a new vacuum** inside. The word 'vacuum' fits the description of what builds up.
- 4. vacuum
The text describes the mechanism of the Bladderwort. After the trap shuts, the cells **pump water out** to reset the trap, which results in **creating a new vacuum** inside. The word 'vacuum' fits the description of what builds up.
- 5. frogs
The text mentions that the **largest** pitcher plants are big enough to **consume** (eat) **whole frogs**. The word 'frogs' completes the sentence about what they can capture and eat.
- 6. TRUE
The statement claims pitcher plants **increase in size** after eating insects. The text confirms that when fed **extra bugs**, the plants **get bigger**. Answer: TRUE.
- 7. TRUE
The statement claims they produce **light-harvesting enzymes** using nutrients from animals. The text explicitly states they take nutrients **from the flesh** to **build light-harvesting enzymes**. Answer: TRUE.
- 8. FALSE
The statement claims carnivorous plants are **more efficient** at photosynthesis. The text states they are **not very good at photosynthesis** compared to plants with ordinary leaves because they lack flat solar panels. This is a direct contradiction. Answer: FALSE.
- 9. NOT GIVEN
The statement claims Venus flytraps are **better adapted** to swamps than **other carnivorous plants**. The text compares carnivorous plants to **‘conventional’ plants**, stating they have an advantage over them. It does not compare Venus flytraps to other carnivorous species. Answer: NOT GIVEN.
- 10. FALSE
The statement claims they find it **difficult to photosynthesise** due to a **lack of sunlight**. The text states the opposite: bogs are **often flooded with sunshine**, allowing them to photosynthesize enough to survive. Answer: FALSE.
- 11. NOT GIVEN
The statement mentions scientists **campaigned** to reduce nitrogen. While the text discusses the **problem** of extra nitrogen from fertilizers, it **does not mention** any campaign by scientists to reduce it. Answer: NOT GIVEN.
- 12. TRUE
The statement says a lot of plants are **sold illegally**. The text confirms that the **black market trade** (illegal selling) is **strong**. Answer: TRUE.
- 13. FALSE
The statement claims **preventing wildfires** is **beneficial**. The text states that the **suppression of wildfires** allows competitors to grow and **outcompete** the Venus flytraps, which is harmful, not beneficial. Answer: FALSE.