Carnivorous plants

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题目与答案

1. Carnivorous Plants

   Darwin's experiments:

   Drosera

   ·He put insects and small amounts of meat onto leaves and observed what happened.

   ·He was amazed that one human hair triggered a response.

   ·1 He understood why the plant did not respond to _____ .

   答案：raindrops

   原文定位：Yet sundews, he observed, ignored raindrops. To react to such a false alarm, he reasoned, would obviously be a "great evil" to the plant

2. 10 Carnivorous plants frequently find it difficult to photosynthesize in bogs due to a lack of sunlight.
   • TRUE
   • FALSE
   • NOT GIVEN

   答案：FALSE

   原文定位：Also, bogs are often flooded with sunshine, so even an inefficient carnivorous plant can carry out enough photosynthesis to survive

3. 11 Scientists have campaigned to reduce the amount of nitrogen that is released into the soil by agricultural practices.
   • TRUE
   • FALSE
   • NOT GIVEN

   答案：NOT GIVEN

   原文定位：Chemical fertilizers used in agriculture and pollution from power plants are adding extra nitrogen to many bogs in North America. Carnivorous plants are so finely adapted to low levels of nitrogen that this extra fertilizer is overloading their systems

4. 12 A lot of exotic carnivorous plants are sold illegally.
   • TRUE
   • FALSE
   • NOT GIVEN

   答案：TRUE

   原文定位：The black market trade in exotic carnivorous plants is strong

5. 13 Preventing wildfires beneficial to the Venus flytrap.
   • TRUE
   • FALSE
   • NOT GIVEN

   答案：NOT GIVEN

   原文定位：The suppression of wildfires by government agencies allows other plants to grow quickly and outcompete the Venus flytraps

6. Biology today:

   Venus Flytrap

   ·2 He demonstrated how leaves close and then, for a short period, act like a _____ .

   ·He noted the structure of leaves ensures small insects are released.

   答案：stomach

   原文定位：He showed that when one of its leaves snapped shut, it formed itself into a temporary "stomach," secreting enzymes that could dissolve the prey

7. Venus Flytrap

   ·If insects come into contact with leaf hairs, their movement produces an electric charge.

   ·3 The charge enters fluid-filled tunnels, causing _____ in the cell walls to open.

   ·Water moves between cells and then the leaf changes from convex to concave, trapping the insect inside.

   答案：pores

   原文定位：Volkov's experiments reveal that the electric charge travels down fluid-filled tunnels in a leaf, which opens up pores in cell membranes

8. Bladderwort

   ·Hairs bend when insects swim past, resulting in opening of a flap.

   ·Water is sucked in.

   ·4 When water is pumped out of bladder cells, a _____ inside. builds up inside.

   答案：vacuum

   原文定位：The cells in the bladder then begin to pump water out again, creating a new vacuum

9. Pitcher Plants

   ·The plants have tube-shaped leaves that insects fall into.

   ·5 Some plants are big enough to capture and eat _____ .

   答案：frogs

   原文定位：Some of the largest have pitchers up to 30cm deep and can consume whole frogs unlucky enough to fall into them

10. 6 Pitcher plants increase in size after they have digested a lot of insects.
    • TRUE
    • FALSE
    • NOT GIVEN

    答案：TRUE

    原文定位：Carnivorous plants clearly benefit from eating animals; when scientists feed pitcher plants extra bugs, the plants get bigger

11. 7 Carnivorous plants produce light-harvesting enzymes with the nutrients they extract from animals.
    • TRUE
    • FALSE
    • NOT GIVEN

    答案：TRUE

    原文定位：Carnivorous plants, however, take nitrogen and phosphorus from the flesh in order to build light-harvesting enzymes

12. 8 Pitcher plants and Venus flytraps are more efficient at photosynthesis than plants with ordinary leaves.
    • TRUE
    • FALSE
    • NOT GIVEN

    答案：FALSE

    原文定位：A pitcher or a flytrap is not very good at photosynthesis because, unlike plants with ordinary leaves, they do not have flat solar panels that can absorb lots of sunlight

13. 9 Venus fly traps are better adapted to the soil of swamps and bogs than other carnivorous plants.
    • TRUE
    • FALSE
    • NOT GIVEN

    答案：FALSE

    原文定位：The poor soil of bogs and swamps, where many carnivorous plants grow, offers little nitrogen and phosphorus, so carnivorous plants enjoy an advantage there over 'conventional' plants