图为小江用显微镜观察小鱼尾鳍内的血液．流动情况，箭头表示血流_爱下问搜题

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问题填空题

图为小江用显微镜观察小鱼尾鳍内的血液．流动情况，箭头表示血流方向，请根据图填写内容：

（1）他在视野中发现了这样一些血管A段是______、B段是______C段是______．

（2）辨别三种血管的理由是：动脉内血液由较______的血管流向较______的血管；静脉内血液由______而分支多的血管汇流入较______的血管；毛细血管内血液中的红细胞一般成______通过．

答案

用显微镜观察小鱼尾鳍时，判断动脉、静脉和毛细血管的依据是：从主干流向分支的血管是动脉，图中血管C是血液由较粗的血管流入较细的血管是动脉；由分支汇集而成的血管是静脉，图中血管A是血液由较细的血管汇入较粗的血管是静脉；B血管允许红细胞单行通过的是毛细血管，起到连接作用．所以C为动脉，A为静脉，B为毛细血管．

故答案为：（1）静脉；毛细血管；动脉

（2）粗；细；细；粗；单行

单项选择题

新华公司存货的日常核算采用毛利率法计算发出存货成本。该企业2008年1月份实际毛利率为25%，本年度2月1日的存货成本为2400万元，2月份购入存货成本为3 000万元，销售收入为5 000万元，销售退回为500万元。该企业2月末存货成本为( )万元。

A．1 525
B．2 025
C．1 650
D．1 650

完形填空

完形填空
I had my first job at the age of thirteen , when a friend of my mother who owned a bookshop hired me for six hours a week to help her in the shop . I was very 36 to earn my own pocket money and my parents 37 interfered (干涉) with how I spent it , even when I was spending it 38 .They believed that by earning money ,spending it ,and learning from the 39 ,I would become more mature (成熟的)and 40 in how to handle work ,relationships with others ,and money.
Like many 41 parents ,my parents also let me and my brothers do things about which they 42 a great deal .When I was sixteen ,for example ,after I finished high school and before I entered university ,I wanted to spend the summer months traveling around 43 .My mother was against the idea of my traveling alone at such a young age, but my father felt that it would be a great 44

for me .In the end , my father won the 45 on the condition that I limited my traveling to France ,my mother’s home, where I had many uncles, aunts and cousins 46 through the country who could 47 shelter and help if I needed them .
Three years later ,my younger brother decided to 48 a year off after his first year in university and travel through the United States and the Caribbean. Again my mother was very worried and not 49 to see my brother leave school, but my father encouraged him and my brother spent a (n) 50 year working his way on trains and ships to 51 his passage to different ports and cities, and discovering many fascinating places and people.
These kinds of experiences are probably 52 for children in many countries but in the US they are fairly common. Most parents start 53 their children at a young age to do small things by themselves .By the time they have finished high school, many American kids have already had 54 jobs and traveled around the US or other countries on their own , have selected the university they plan to attend , maybe even have decided on their future 55 ,and so on .

D．responsible

D．possibility

A．sending out

C．carrying out

D．spreading out