试题

试题 试卷

logo

题型:实验探究题 题类:常考题 难易度:普通

山东省肥城市石横镇初级中学2016-2017学年七年级下学期期末训练生物试题

丽丽同学在“测定某种食物中的能量”探究实验中想测定花生仁与核桃仁哪个含能量多。他们小组是这样进行实验的:取两支相同试管装入同样高度的水,取一个花生仁、半个核桃仁在酒精灯上点燃后,分别放在试管下方,给水加热,等花生仁、核桃仁完全燃烧后,分别测出两个试管中水的温度,再经过计算,得出结论。

(1)、请问他们的结果准确吗?。为什么?原因是

(2)、小伟同学做的是测定花生仁中含有多少能量,但小伟发现他测定的数据小于标准数据,请你帮小伟分析有可能的原因?

举一反三
选取三枝同一植物的长势相同的枝条分别标记为A、B、C, 作如下表的处理后,分别插入相同大小的、盛有等量蒸馏水的量筒中,并以石蜡油覆盖密封水面,置于适宜环境条件下。2小时后观察记录各组量筒中蒸馏水的减少量(说明:涂抹凡士林能堵塞叶片相应部位气体进出的通道)。请回答下列问题:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 

枝条编号

枝条处理

蒸馏水减少量

A

不作任何处理

2mL

B

凡士林涂抹所有叶片下表面

0.5 mL

C

除去枝条上的所有叶片

0 mL

返回首页

试题篮