سؤال قراءة ستيب محلول — الإشارة والمرجعية (تدريب 4667)

(1) Like all insects, ants have six legs. Each leg has three joints. The legs of the ant arc very strong so they can run very quickly. If a man could run as fast for his size as an ant can, he could run as fast as a racehorse. Ants can lift 20 times their own body weight. An ant brain has about 250.000 brain cells. A human brain has 10 billion brain cells, so a colony of 40.000 ants has collectively the same number of brain cells as one human brain. (2) The average life expectancy of an ant is 45-60 days. Ants use their antennae not only for touch, but also for smell the head of the ant has a pair of large, strong jaws. The jaws open and shut sideways like a pair of scissors. Even adult ants cannot chew and swallow solid food. Instead, they swallow the juice which they squeeze from pieces of food and throw away the dry part that is left. (3) The ant has two eyes, each of which is made of many smaller eyes, so they are called compound eyes. The abdomen of the ant contains two stomachs. One stomach holds the food for itself and the second stomach is for food to be shared with other ants. Like all insects. the outside of their body is covered with a hard armor called the exoskeleton. Ants have four distinct growing stages, the egg. larva, pupa and the adult are classified as a special group of wasps. (4) There are over 10.000 known species of ants. They all live in social groups usually called colonies. A colony has one or more queens. The sole duty of a queen is to lay eggs. The worker ants, all of whom are female, cannot produce eggs; they take care of the queen and the eggs she produces. Since the worker ants are sterile, their roles within the colony might be looking after the young, providing food, or defending the nest from unwanted visitors. Ants are clean and tidy insects, so some worker ants are given the job of taking the rubbish from the nest and putting it outside in a special rubbish dump. Each colony of ants has its own smell. In this way, intruders can be recognized immediately. Many ants, such as the red species, have stingers which they use to defend their nest. However, some ants - like black ants and wood ants - have no stingers, but can squirt acid to defend themselves and the colony. (5) Ants are interesting creatures. They have very tiny bodies but live in a complex social community. They are not simply pests, as many people think; in point of fact, they represent a positive example of how planning and teamwork should work in our societies.