阅读理解。
Look closely at the palms of your hands and fingertips. See all the tiny lines? Each of us is born with a
unique set of prints, but it may surprise you to learn why we have them. Palm lines are not for fortune-tellers
to figure out how long we will live, nor are fingerprints there to make a policeman's job easier. In fact, the
lines and circles that decorate our hands and feet are an evolutionary gift from nature, and they serve two
important functions.
Our prints are made of raised and lowered skin. The raised areas function somewhat like the tread (纹)
of car tires or the rubber soles (胶底) of our running shoes. When we touch something that is wet, water
moves from these "hills" into the "valleys", which means some surfaces on our skin remain relatively dry.
This is useful, for it allows us to better grip the things we want to hold.
Our prints help us hold on, but they also have a secondary function: protection. The raised areas serve
as buffers (缓冲物) between our skin and an object, keeping us from getting hurt every time we grip the
hard surface of a bottle or a baseball bat. This is the same reason why, when we walk too far or wear
uncomfortable shoes, we get blisters on the soft skin of our ankles, but never on our heels, like our palms
and fingers, which have prints to protect them.
It is the random (任意的) flow of fluids inside our mothers' wombs that causes these useful patterns
to form on the surface of our hands and feet. Because they are formed randomly, each person's prints are
unique, which makes prints accidentally useful as a means of distinguishing between people. Even identical
twins have different prints, which means that no mistakes can be made in determining who did a crime,
provided fingerprints or toe prints were left at the scene.
1. Where can't you find the tiny lines ____?
A. Palms
B. Fingerprints
C. Heels
D. Ankles.
2. Which of the following is NOT mentioned in the passage?
A. The tiny lines are the results of evolution.
B. From one's fingerprints, we can guess his character.
C. Different people have different prints in their fingertips.
D. The prints play an important role in our life.
3. Which of the following statements is true according to the passage?
A. Fingertips can help us hold on to things better.
B. There are no prints on our heels.
C. The prints can make our palm dry.
D. Prints can protect us from getting hurt.
