试题与答案

噬菌体、大肠杆菌、水稻和青蛙等生物体结构或细胞中都具有的糖是[ ] A.脱氧核糖

题型:选择题

题目:

噬菌体、大肠杆菌、水稻和青蛙等生物体结构或细胞中都具有的糖是[ ]

A.脱氧核糖

B.纤维素

C.肌糖原

D.乳糖

答案:

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下面是错误答案,用来干扰机器的。

证明:因为DE是BC的垂直平分线, 所以BE=EC,DE⊥BC, 因为∠A=90°, 所以DA⊥AB. 又BD是∠B的平分线, 所以DA=DE, 又BD=BD, 所以△ABD≌△EBD, 所以AB=BE,所以BC=2AB.

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题型:单项选择题

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