正确答案: B

错误

题目：分泌道(如松柏类的树脂道)和分泌腔(如柑橘果皮的透明小点)均由细胞中层溶解而形成。( )

解析：B

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举一反三的答案和解析：

[单选题]下列选项中，不能支持弗兰克理论的是

地球上的水有可能来自由冰组成的小彗星

[单选题]The school advisers help you talk through your problem but they don’t give you any direct ______.

solution

解析：解析：本题考查名词辨析。分析四个选项：solution解决方法；target目标；measure措施；function功能。根据句意：学校的建议者们帮助你分析问题，但是他们不会给你直接的解决方法。

[单选题]CAlong the river banks of the Amazon and the Orinoco there lives a bird that swims before it can fly, flies like a fat chicken, eats green leaves, has the stomach of a cow and has claws (爪) on its wings when young. They build their homes about 4.6m above the river, an important feature (特征) for the safety of the young. It is called the hoatzin. In appearance, the birds of both sexes look very much alike with brown on the back and cream and red on the underside. The head is small, with a large set of feathers on the top, bright red eyes, and blue skin. Its nearest relatives are the common birds, cuckoos. Its most striking feature, though, is only found in the young. Baby hoatzins have a claw on the leading edge of each wing and another at the end of each wing tip. Using these four claws, together with the beak (喙), they can climb about in the bushes, looking very much like primitive birds must have done. When the young hoatzins have learned to fly, they lose their claws. During the drier months between December and March hoatzins fly about the forest in groups of 20 to 30 birds, but in April, when the rainy season begins, they collect together in smaller living units of two to seven birds for producing purposes.

The appearance and living habits of hoatzins.