题干

下列关于人体血压调节的叙述中,错误的是(  )

A:心排血量不变,血管管径变小,则收缩压也会相应升高

B:动脉血压突然降低时,引起交感神经活动加强,动脉血压回升

C:心舒期血液向外围流动的速度减慢,则舒张压降低

D:长期过度紧张,可使大脑心血管中枢平衡失调,导致血压升高

上一题 下一题 0.0难度 选择题 更新时间:2017-10-16 10:19:25

答案(点此获取答案解析)

C

同类题2

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

    For many people, a special sale is just too attractive to walk away from. ____ But with sales items, how can you be sure you're really getting a good deal? If you understand some sales tricks, you will be able to make smart choices.

    Some tricks have been used by shopkeepers for ages. ____ For example, if an item is US$11.99 instead of US$12.00, you'll feel like you're spending less money.

    Sellers sometimes reduce items by a certain amount. ____ That means that even with the discount, you may still pay more than the original price.

    Shopkeepers clearly understand what makes you want to buy their products. But with a little preparation, you can avoid being cheated.

Tips for shoppers

*Always compare prices before buying anything.

*____ The more focused you are, the easier it is to make wise decisions.

*Don't shop when you are hungry. Studies show that you'll usually buy more than you originally planned.

*____ First ask yourself: Do I have the money to buy it? Will I use it? If not, walk away, but if so, go for it! That way you'll still feel good after you take your item home.

A.Know what you're looking for.

B.Watch for“Buy one, get one free”sales.

C.And that makes shop owners very happy!

D.One of the oldest is to make prices end in 99.

E.Don't buy something just because it's on sale.

F.Check for sales ads in the newspaper or online.

G.But before the sale begins, sellers might mark the prices higher.