[简答题]When can procedures subjecting animals to distress be used

[简答题]When can procedures subjecting animals to distress be used

[简答题]Questions 30-39 The response of most animals when suddenly faced with a predator is to flee. Natural selection has acted in a variety of ways in different species to enhance the efficacy of the behaviors, known as “ flight behaviors” or escape behaviors, that are used by prey in fleeing predators. Perhaps the most direct adaptation is enhanced flight speed and agility. Adaptations for speed, however, are likely to require sacrifices in other attributes, so we might expect only some species to adopt a simple fast flight strategy. Another way of enhancing the effectiveness of flight is to move in an erratic and unpredictable way. Many species, like ptarmigans, snipes, and various antelopes and gazelles, flee from predators in a characteristic zigzag fashion. Rapid unexpected changes in flight direction make it difficult for a predator to track prey. In some species, like the European hare, erratic zigzag flight might be more effective in the presence of predators that are faster than t
A. A．encourage
B．resist
C．increase
D．reveal

[填空题]

What can the animals live on
These animals can live on （）

[单项选择]When can I have my holidays（）
A. After December 24.
B. It’s too hot in June.
C. My pleasure.
D. No problem.

[填空题]

When can we do running？
We can do it at （）.

[单项选择]When can I take my winter vacation（）
A. It’s too hot in June.
B. In East Europe.
C. In the countryside.
D. After December 24.

[单项选择]

Some desert animals can survive the summer heat and dryness because they are very unusual. The camel, for example, can experience and bear an increase in the temperature of its body and its blood of 9°C without anything bad happening to it. In addition, it can drink a lot of water at one time; then store enough water in parts of its body to supply its needs for two weeks or more. The kangaroo rat, on the other hand, gets all the water it needs from water that it produces when it breathes. However, most animals need to maintain a fairly constant body temperature, and will die if it rises more than 5°C. Therefore, they need to find some way to stay away from the heat of the summer sun. Nor can many animals either store or produce water in their bodies, as the camel and kangaroo rat can. So they must find ways to keep their bodies from losing water because of the heat. Because very few desert animals can survive the high temperature of a typical summer’s day, most of t
A. a very low body temperature
B. only a little change in body temperature
C. a big increase in body temperature
D. a constant change in body temperature