题干

下列关于人体组织的叙述,错误的是(  )

A:血液和骨组织属于结缔组织

B:皮肤的分泌物具有杀菌作用,属于保护组织

C:肌肉组织具有收缩和舒张的功能

D:神经组织主要由神经细胞构成,能够感受刺激,传导神经冲动

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答案(点此获取答案解析)

B

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任务型阅读

    It is now mandatory(强制) for drivers or passengers to wear seatbelts while in a car in all states. In addition, it is also mandatory for kids of be in some kind of specialized car seat. Given the strict requirements in other vehicles, why don't buses have seatbelts?

    The main answer, at least for school buses, is that seatbelts do not make school buses safer. Overall, traveling on school buses is the safest way to travel—40 times safer than riding in a car—with only a handful of deaths occurring to passengers on school buses every year. The seats on the school bus are placed very close to each other and have high backs that are thickly padded. As a result, in an accident the students would be propelled forward a very short distance into a padded seatback that in a way is like an airbag. In addition, the fact that people sit high off the ground on school buses also makes it safer to travel on them.

    While school buses feature high backed seats and elevated seating locations, the same cannot be said of city buses. However, from a practical angle, there's little need to require seatbelts on city buses. Although the design of the modern low—floor city bus is less safe than the design of school buses, the fact that city buses rarely travel at speeds greater than 35 miles per hour means that any collision is likely to be small, Also, given that most trips on city buses are short and that many trips have standing passengers, the presence of seatbelts will make even less of a difference.

    Another answer why buses do not have seatbelts is cost. It is estimated that adding seatbelts to buses would add between $8,000 and $15,000 to the cost of each bus. In addition, seatbelts would take up room currently used as seats, meaning that each bus would have fewer seating places. The additional room in the bus taken up by seatbelts would mean that bus fleets would have to increase by as much as 15% just to carry the same number of people. Such an increase would be especially difficult in cities that experience overcrowding on their vehicles.

    Regardless of whether their passengers have seatbelts, all buses provide seatbelts for drivers and most bus companies make their drivers wear seatbelts in order not to be influenced by a collision.

Why don't buses have seatbelts?

Topic

Everyone is ____to wear their seatbelts in a car while no seatbelts are provided for passengers on buses.

____

School buses:

●Seatbelts make no____.in improving the safety of the school bus.

●Traveling on school buses is safe thanks to their seats with high padded backs, which can____the students from danger because they are propelled forward into them in a collision.

●Sitting high off the ground on school buses also ____to the safety

City buses:

●Their low traveling speed reduces the risk of a collision

●City buses tend to travel a short ____

●Many passengers stand while on a city bus, making seatbelts ____

●Fixing seatbelts on buses can____ in an increase in cost.

●Seatbelts can also limit the number of seating places by____ room on a bus.

●As a result, an increasing number of bus fleets are required to carry the same number of people.

A rule

All buses provide seatbelts for drivers, who should wear seatbelts to____ the impact of a collision.