问题 选择题

在呼气时,膈肌和胸腔容积的变化是                 (  )

A.膈肌收缩,胸腔容积缩小

B.膈肌舒张,胸腔容积增大

C.膈肌收缩,胸腔容积增大

D.膈肌舒张,胸腔容积缩小

答案

答案:D

题目分析:呼吸运动是由于呼吸肌的收缩与舒张引起的,膈肌和肋间肌舒张时,使得胸腔体积缩小,肺内气压增大,气体从肺流向外界,引起呼气,当膈肌和肋间肌收缩时,胸腔体积增大,肺内气压减小,气体由外界进入肺部,引起吸气。故选D。

写句子
阅读理解

阅读理解

     After winning a big game, athletes are often asked how they attained that success.Most say their

achievement is the result of gruelling hard work and intense practice.Usually athletes say how hard it

is to win the big games.At the opposite end of the spectrum, however, is the fact that losing the big

game, or, in my case, all the games, can be even tougher.

     From the spectators'point of view, last year's basketball season for my high school team was

nothing short of an embarrassment.And while 0 and 20 is certainly nothing to be proud of, that season

had a bigger impact on me than any other, and probably more than any season since.

     As a team captain, I knew it probably wouldn't be the easiest year, but did I ever think we would

lose every game?Of course not.Since six of our top players had graduated, it was clear that we were

a young team who would struggle.The struggle began earlier than expected, though, as our team's

starting center was suspended for the season, and two key members decided to quit after two weeks.

At some point, quitting probably passed through every player's mind, but, in the end, we all stuck it

out, vowing to work even harder.

     Then there came a time when even our own coach had given up on us.Personally, I felt like it was

no longer worth giving my all.I thought, if even the coach doesn't believe in us, why should I?But just

as my hope began to fade, a teammate called a meeting.He said, "Nobody thinks we're going to win,

and heck, we may not, but, as teammates and friends, we_owe_it_to_each_other_to_give_it_our_all

_every_game."

     Sure, it was a little clich? (陈旧的), but it was that moment that taught me how to be a leader.It hit

me then that I may have been a captain, but I, like others in my position, certainly didn't deserve the

role.As a leader you can never quit on the team who looks up to you.It is one thing to be named

captain and feel great and go through the motions, but it is quite another to be a real captain and make

sure everyone works to their potential all the time.

     I am sure it is great to go through high school without losing and bringing home awards.But in all

honesty, I relish the fact that my team lost every game last year.It may not help me to become a better

basketball player, but it already has made me a better leader and person.

1. What was the biggest problem with the author's team last season?

A. Several key members were unable to play the games.

B. Their coach no longer wanted to instruct them.

C. There were no actual leaders on the team.

D. Most of players lost hope and wanted to quit.

2. In the text, the author seems to suggest that a good leader should________.

A. be confident about himself

B. make sure everyone goes all out

C. work hard to win the games

D. feel great about his team

3. By saying "we owe it to each other to give it our all every game."(Paragraph 4) the teammate

    means that all of them should________.

A. be responsible for the losses

B. try their best on the court

C. feel thankful for what they've done

D. get together to win every game

4. What is the main idea the author aims to express in the text?

A. Success is the result of hard work.

B. A friend in need is a friend indeed.

C. One can learn something from the failure.

D. A real leader should never give up.