题干

下面有关动物生命活动调节的叙述中,正确的是

A:给正常小鼠每天饲喂一定量的甲状腺激素,3天后,该小鼠新陈代谢增强,血浆中促甲状腺激素含量减少,促甲状腺激素释放激素含量增加

B:给正常小鼠饲喂一定量的胰岛素,一段时间后,小鼠会出现四肢无力,活动减少,甚至昏迷等低血糖症状

C:由于递质只存在于突触小体内,只能由突触前膜释放,然后作用于突触后膜,使后一个神经元发生兴奋或抑制,故神经元之间兴奋的传递只能是单方向的

D:将大白鼠从25℃移至0℃的环境中,由于环境温度下降,大白鼠出现的生理反应是耗氧量减少,体表血管收缩,散热量减少

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C

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Walk For Charity

Dear Friend,

    Please join us for our annual Walk For Charity.Starting in Weldown,you and your friends can choose a delightful 10,20 or 30 kilometers' route.

    The money raised will provide support to help people all over the world.Start collecting your sponsors now and then simply come along on the day.Please read the instructions below carefully,especially if you require transport to and from Weldown.

    See you on Sunday 15 April.

    V Jessop: Walk coordinator

    PS.Well done to last year's walkers for helping to raise a grand total of £21,000.The money has already been used to build a children's playground.

    START TIME:

    30 km: 8-10 am      20 km: 8-10:30 am      10 km: 8-11:30 am

    The organizers reserve the right to refuse late-comers.

    CLOTHING should be suitable for the weather.If rain is forecast,bring some protection and be prepared for all possibilities.It is better to wear shoes that have been worn in,rather than ones that are new.

    ROUTE MAPS will be available from the registration point.The route will be sign-posted and arranged.Where the route runs along the road,walkers should keep to one side in single file,facing oncoming traffic at all times.If you need help along the route,please inform one of the staff.

    Free car parking is available in car parks and on streets in Weldown.

    BUSES:

    For the 10 and 20 kilometers' routes,a bus will be waiting at Fenton to take walkers back to Weldown.The bus will leave every half hour starting at midday.The service is free and there is no need to book.