问题 多项选择题

关于脊髓解剖结构的描述,哪些是正确的()

A.颈膨大包括颈5至胸2,发出支配上肢的脊神经

B.腰膨大包括腰1至骶2,发出支配下肢的神经

C.马尾由腰2至尾节共10对神经根组成

D.颈8至腰2及骶2~4有侧角

E.骶髓2~4的侧角为脊髓副交感中枢,发出纤维支配膀胱、直肠和性腺功能

答案

参考答案:A, B, C, D, E

解析:

脊髓的外部结构:脊髓呈连续性分布,其表面并无节段界限。脊髓有两个膨大,称为颈膨大和腰膨大。颈膨大包括C5~T2,发出的神经根支配上肢;腰膨大包括L1~S2,发出的神经根支配下肢。

马尾由L2至尾节共10对神经根组成。

脊髓的内部结构:脊髓灰质在中央管前后的连合部分别称为灰质前连合和灰质后连合,其他部分组成前角和后角。前角内含运动神经细胞,属下运动神经元;后角含传递痛、温度觉和部分触觉的Ⅱ级感觉神经元。C8~L2和S2~S4还有侧角。C8~L2的侧角内主要是交感神经细胞,发出纤维经前根、通过交感神经径路支配和调节内脏及腺体的功能。C8~T1的侧角发出的交感纤维,一部分沿颈内动脉进入颅内,支配同侧瞳孔扩大肌、睑板肌、眼眶肌;另一部分支配同侧面部血管及汗腺。S2~S4的侧角为脊髓副交感中枢,发出纤维支配膀胱、直肠和性腺。

答案选A、B、C、D、E。

单项选择题
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阅读下面短文,按照句子结构的语法性和上下文连贯的要求,用下面文本框中所给单词填空
(请用字母来填空)。(文本框中所给单词或词组有多余)
A. effort  B. provide  C. for  D. a  E. that  F. which  G. religious  H. attend  I. made  K. go  L. through
     Each fall almost 50 million young Americans walk 1______ the doorways of about 100 000 elementary
and secondary schools for the start of 2______ new school year. Filling classrooms from kindergarten to
the 12th grade, they attend classes for an average of five hours a day, five days a week, until the beginning
of the following summer.
     About 85% of American students 3______ public schools (schools supported by American taxpayers).
The other 15% attend private schools, 4______ which their families choose to pay special attendance fees.
Four out of five private schools in the United States are run by churches, synagogues (犹太教会堂) or
other religious groups. In such schools, 5______ teachings are a part of the curriculum(课程), which also
includes the traditional academic courses of reading, mathematics, history, geography and science.
     U.S. Department of Education makes every 6______ to educate an entire national population. The goal
is-and has been since the early decades (a period of ten years) of the republic-to achieve universal literacy
(able to read and write) and to 7______ individuals with the knowledge and skills necessary to promote both
their own individual welfare (福利) as well as 8______ of the general public. Though this goal has not yet
been achieved, it remains an ideal toward 9______ the American educational system is directed. The progress
which has been 10______ is notable both for its scope (范围) and for the educational methods which have
been developed in the process of achieving it.