托福阅读真题精选-11
【摘要】 虽然2月考试暂时取消，之后考试视情况而定，但是托福备考生不宜懈怠，下面是小编整理的托福阅读真题精选-11的内容，让我们一起来看看吧。
经与教育部考试中心研究商讨决在全国范围内取消2月所有各类托福考试，考试费将全额退还至考生个人报名账户。虽然2月考试暂时取消，之后考试视情况而定，但是托福备考生不宜懈怠，下面是小编整理的托福阅读真题精选-11的内容，让我们一起来看看吧。
Questions 30-40
The smooth operation of an ant colony depends on ten to twenty different signals, most of which are pheromones (chemical signals triggering behavioral responses). It is estimated that red fire ants employ at least twelve different chemical signals. The simples Line of these is the carbon dioxide from the respiration of an ant cluster, a chemical that acts as (5) a pheromone to promote aggregation. Workers move toward a source of carbon dioxide, resulting in solitary ants moving to join a group. At the other extreme, the most complex of the fire ants' signals is probably colony odor, by which the workers of a particular colony or nest identify another worker as local or foreign. Each ant nest has its own odor as a result of its location, history, and local food supply. The resident ants pick up this (10) odor on their bodies, so that ants of the same species, but from different nests, have different colony odors. This allows ants to identify intruders and maintain colony integrity.
Fire ants also make use of an alarm pheromone to alert workers to an emergency, and their scouts lay down a trail pheromone as a guide during mass migrations. A fire ant (15) queen emits a chemical signal that identifies her to the colony's workers. They respond by scurrying to gather around her. The decomposing corpse of a dead ant also generates a signal, to which workers respond by eliminating the corpse from the nest.
Ants provide examples of both public (accessible to other species) and private messages. One of their most important private messages concerns food, for a food source (20) is worth keeping secret. Each species marks its trails with signals that are meaningless to others, so that an ant crossing a trail left by another ant species typically notices nothing.
On the other hand, a secret signal to mark a dead body is unnecessary. Many kinds of ants perceive a natural decomposition product of dead insects as a signal to remove a corpse. If an outsider recognizes this message and moves the body, no harm is done.
30. What aspect of ants does the passage mainly discuss?
(A) The relationship between the queen and the worker ants
(B) Ways in which ants use chemical signals
(C) Methods ants use to identify food sources
(D) The importance of respiration in the production of ant pheromones
31. The phrase "smooth operation" in line 1 is closest in meaning to
(A) daily activity
(B) effective functioning
(C) delicate balance
(D) permanent location
32. According to the passage, carbon dioxide serves which of the following functions for fire ants?
(A) It protects the queen.
(B) It attracts other ant species.
(C) It informs workers of possible danger.
(D) It encourages the ants to gather together.
33. The word "cluster" in line 4 is closest in meaning to
(A) organ
(B) activity
(C) group
(D) cycle
34.According to the passage, each nest has a distinct odor that allows its inhabitants to
(A) find the location of the nest in the dark
(B) distinguish worker ants from other ants
(C) distinguish foreign ants from resident ants
(D) signal other inhabitants when foreign ants attack
以上就是托福阅读真题精选-11的具体内容，我们将根据疫情防控的进展情况，动态更新并通知2020年2月后雅思考试的报名和考试安排，更多资讯关注考必过网站。