Comprehension Skills for Science : Who can answer the questions based on this passage?

Elaborate Carnivorous Plants Prove To Be Kin

1. The Venus flytrap has a muddled family history. Charles Darwin thought this elegant bug eater from
the southern United States had close ties to a European aquatic weed called the waterwheel. A
century later, researchers decided that the waterwheel’s closest kin was not the Venus flytrap but the
terrestrial sundew, which also dines on insects. Now a DNA analysis of these botanical carnivores
suggests that Darwin’s hunch was right after all.

2. In many ways, this revised family history makes sense, comments Mark Chase, a plant systematist at
the Kew Royal Botanical Gardens in Surrey, U.K., even though he once suggested otherwise. Of all
the plants that feast on animals, waterwheels and Venus flytraps “have taken carnivory to the
extreme,” he notes. Each has leaves reshaped into traps that snap shut. Now that their close
relationship is “nailed down, it sets the stage for people to ask more intelligent questions about how
these mechanisms evolved,” Chase points out.

3. Carnivorous plants have come up with a variety of ways to snare their prey: pools of water for
drowning unlucky visitors, sticky surfaces that work like flypaper, or “snap traps” that clam down on
morsels in milliseconds. Sundews are flypaper predators; waterwheels and Venus flytraps depend on
snap traps. All use their prey not as a food source but to provide minerals.

4. Evolutionary biologists have long speculated about how these features evolved. In the late 1800s,
Darwin picked up on similarities in the stamens and pistils – a flower’s reproductive parts – of
waterwheels and the Venus flytrap and suggested that these two plants were closest kin. However, in
the early 1990s, Chase and his colleagues threw a fly in the ointment, so to speak, when they
compared the DNA of about a dozen carnivorous plants and took a closer look at their morphology.
They had no DNA from waterwheels and so relied solely on morphology (Science, 11 September
1992, p. 1491).

5. The 20th century study led researchers to conclude that they should lump the sundew in with the
waterwheel and push the Venus flytrap out of the tight-knit group. This family tree had evolutionary
implications, says Richard Jobson, a plant systematist at Cornell University in New York. Snap traps
might have evolved twice, once in the waterwheel and once in the Venus flytrap.

6. Now a 21st century DNA analysis tells a different evolutionary story. Jobson, Kenneth Wurdack of
the Smithsonian Institution in Maryland, and Kenneth Cameron of the New York Botanical Garden
have compared four genes instead of the one studied in the 1990s. They conclude that even though
the Venus flytrap is terrestrial and the waterwheel aquatic, the world’s only two snap-trapping plants
are nonetheless siblings. The sundew is no closer than a cousin, sharing a common ancestor much
earlier in time, the group reports in the September issue of the American Journal of Botany.

7. Cameron and his colleagues contend that this evolutionary arrangement suggests that snap traps
evolved only once. Moreover, “our results demonstrate that snap traps evolved from flypapertrapping
plants,” he says. They also think that among snap trappers, the Venus flytrap came first.

8. Chase thinks the snap-trap story might be more complicated than it now looks. The two species “don’t
live in the same parts of the world,” he explains, and although fossils show that the waterwheel was
once common throughout Eurasia, the Venus flytrap is known to grow only in North and South
Carolina. That leaves open the question of where the snap-trap plants got started and how they
spread.

Question 1
The phrase carnivorous plants in the title implies that
1 some plants are plant eaters.
2 some animals are plant eaters.
3 all plants are meat eaters.
4 some plants are meat eaters.

Question 2
This article aims to
1 clarify the relationship between the Venus flytrap and other carnivorous plants.
2 clarify the relationship between the sundew and the waterwheel.
3 provide the evolutionary history of the sundew.
4 clarify the relationship between snap traps and flypaper traps.

Question 3
The function of the word but in the 3rd sentence of paragraph 1 is to signal
1 a cause and effect relationship.
2 contrasting information.
3 chronological order.
4 examples.

Question 4
In paragraph 2 the sundew is described as terrestrial because it is a
1 land dwelling plant.
2 territorial plant.
3 celestial plant.
4 water-dwelling plant.

Question 5
Which of the following signpost words or phrases in paragraph 2 is used to signal ‘change and contrast’?
1 in many ways
2 now
3 even though
4 otherwise

Question 6
‘Snap traps’ is written both with a hyphen and without it ( see paragraphs 3,5,6,7 and because
1 both are equally correct.
2 the editing of the published article was inconsistent.
3 it is hyphenated only when it functions as an a