Ielts reading question-type based tests true false not given matching headings



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aslanov

 
B. 
The first crocodile-like ancestors came into existence approximately 230
 
million years ago, and 
they had many of the features which make crocodiles
 
natural and perfect stealth hunters: streamlined body, 
long tail, protective
 
armour and long jaws. They are born with four short, webbed legs, but this
 
does not 
mean that their capacity to move on the ground shall ever be
 
underestimated. When they move, they are so 
fast that you won’t even have
 
any chance to try making the same mistake again by getting too
 
close, 
especially when they’re hunting.
 
 
C. 
Like other reptiles, crocodiles are poikilothermal animals (commonly known as coldblooded, 
whose body temperature changes with that of the surroundings) and consequently, require exposure to 
sunlight regularly to raise body temperature. When it is too hot, they would rather stay in water or shade. 
Compared with mammals and birds, crocodiles have a slower metabolism, which makes them less 
vulnerable to food shortage. In the most extreme case, a crocodile can slow its metabolism down even 
further, to the point that it would survive without food for a whole year, enabling them to outlive mammals 
in relatively volatile environments. 
D. 
Crocodiles have a highly efficient way to prey catching. The prey rarely realises there might be a 
crocodile under the water because the crocodile makes a move without any noise or great vibration when 
spotting its prey. It only keeps its eyes above the water level. As soon as it feels close enough to the victim
it jerks out of the water with its wide open jaws. Crocodiles are successful because they are capable of 
switching feeding methods. It chases after fish and snatches birds at the water surface, hides in the waterside 
bushes in anticipation of a gazelle, and when the chance to ambush presents itself, the crocodile dashes 
forward, knocks the animal out with its powerful tail and then drags the prey into the water to drown. 
E. 
In many crocodilian habitats, the hot season brings drought that dries up their hunting grounds, 
leaving it harder for them to regulate body temperatures. This actually allowed reptiles to rule. For instance
many crocodiles can protect themselves by digging holes and covering themselves in mud, waiting for 
months without consuming any food or water until the rains finally return. They transform into a quiescent 
state called aestivation. 
F. 
The majority of crocodilian is considered to go. into aestivation during the dry season. In a six-year 
study by Kennett and Christian, the King Crocodiles, a species of Australian freshwater crocodiles, spent 
nearly four months a year underground without access to water resources. Doubly labelled water was 
applied to detect field metabolic rates and water flux, and during some years, plasma fluid samples were 
taken once a month to keep track of the effects of aestivation regarding the accumulation of nitrogenous 
wastes and electrolyte concentrations. 

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