Most people are born with straight hair, but why are there people born with curly hair? It may look like a simple question that we can easily answer, but the answer is not as simple as it seems.
The colour and shape of your hair are decided by your genes(基因). Whether you have straight hair or curly hair comes from your parents' genes. "If both your parents give you the curly version(版本) of the gene, you end up with curly hair, " Barry Starr, a geneticist at Stanford University, US, told Popular Science. If both give you the straight version you end up with straight hair. And if one gives you curly genes and the other straight, you could end up with either. But how does DNA work on a single hair?
Scientists show that the curls of hair depend on the nature of its follicle(毛囊). When a follicle is asymmetrical(不对称的), the hair that it produces is curl. Another point is that the follicle of curly hair has a hooked(钩状的) end. The more hooked the follicle is, the curlier the hair is. Follicles for straight hair have no hooks.
But even if you are born with straight hair, there are some ways that straight hair can turn curly. Scientists have found that a cell(细胞) called EGFR in follicles appears to control the growth of hair. For example, certain cancer medicine that stop these cells may cause a patient to develop curly hair as a side effect.
( )1. The number of people born with curly hair is___ that of people born with straight hair.
A. larger than B. smaller than
C. twice as large as D. as big as
( )2. From Paragraph 2, we can know that ________.
A. our genes can decide the length of our hair
B. our parents' genes decide whether we have straight or curly hair
C. Barry Starr is a geneticist from Popular Science
D. If one boy's parents have straight hair, he may have curly hair
( )3. Which of the following statements is TRUE according to Paragraph 3?
A The nature of hair's cells decides the curls of hair.
B. If a follicle is asymmetrical, the hair produced is straight.
C. If follicles for a girl's hair have no hooks, she may have curly hair.
D. If follicles for a girl's hair have more hooked ends, she has curlier hair.
( )4. The passage is possibly from_______.
A a novel B. a poem
C. a science book D. a news report
1B 2B 3D 4C
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A wedding(婚礼) Invitation
You’re invited to the wedding of Carrie and Henry at St John’s Church(教堂), on Saturday January 24th at 3:30 p.m. and dinner at the Blue Sky Restaurant, at 6:00p.m.
R.S.V.P: December 29th
Dear Joe, I’m so excited and I have to enjoy the news with you. Today is December 23rd, I got a very special invitation from Carrie before Christmas Day(圣诞节). Do you remember the party for the Sydney group at Henry’s house? And do you remember my best friend, Carrie? Well, guess what? Carrie and Henry are getting married? It’s so romantic! Love is here! Carrie and Henry are having a big wedding at St. John’s Church. Monica and James are going to their wedding. Oh, I can’t wait to enjoy it. I got the invitation and it is for two people. Can you come to the wedding with me? Carrie and Henry are going to Suzhou for their honey moon(蜜月). I’m buying them a camera for their wedding. But before the wedding, I’d like to get my hair cool and buy a pink dress first. Call me at 9:00 a.m., on Friday, January 23rd, OK? Maria |
36. Maria got this wedding invitation from .
A. Carrie. B. Joe. C. Monica. D. James
37. Monica and James are taking part in the wedding on .
A. Friday morning. B. Friday afternoon. C. Saturday morning. D. Saturday afternoon.
38. What does “getting married” mean in Chinese?
A. 参加聚会 B. 过圣诞节 C. 做礼拜 D. 结婚
39. The friends to the wedding party are going to have dinner .
A. in Suzhou. B. at Henry’s house C. at St John’s Church D. at the Blue Sky Restaurant
40. From the invitation card, we know that .
A. Monica is having fun in Suzhou. B. they are having the wedding in January.
C. Monica is going to buy a camera for Joe D. the wedding dinner starts at 7:00 p.m.
Do you have pen pals? I have three pen pals from three different countries. They are Tom, Ella, and Molly.
Tom comes from Australia. His favorite subject is P.E., because he likes playing soccer best and he can play it in P.E. classes. He has a sister and a brother.
Ella is an American girl. Of all her subjects, she likes Chinese best. She often writes to me in Chinese. Her favorite sport is volleyball.
Molly lives in Tokyo. She likes learning Chinese, too. But her favorite subject is math. When she has time, she likes playing tennis best. She is a very clever girl.
I love them very much.
根据短文内容,将表格补充完整。
Name | From | Living place | Favorite subject | Favorite sport |
Tom | Australia | / | 1. ______ | soccer |
Ella | 2. _____ | / | Chinese | 3. _____ |
Molly | / | 4. ____ | 5. _____ | tennis |