题干

实验操作题

水是生命之源.植物的生命活动离不开水,同时还要不断地向外散失水分,水分的散失受多种因素的影响.小刚同学想:叶片面积与植物散失水分有关系吗?针对这一疑问,他设计了如下实验:

①在一株生长健壮的绿色植物上选取两段枝叶相似的枝条,一段保留全部叶片,另一段去掉大部分叶片.

②用量筒量取等量清水,分别注入编号为甲、乙的两个锥形瓶里.

③把两段枝条分别插入两个锥形瓶里,并用脱脂棉塞紧瓶口.

④将两个实验装置至于相同光下照射一段时间,取出锥形瓶中的脱脂棉和枝条.

⑤用量筒分别测量两个锥形瓶中剩余的清水量,计算实验前后两个装置内的清水量的差值,记录在表中:

清水量(毫升)

实验装置

初始量(毫升)

最终量(毫升)

差值(毫升)

甲




乙




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    A family is a collection of people who share the same genes(基因)but cannot agree on a place to pull over for lunch. Ed and I, plus his parents and sister Doris and eight-year-old niece Alisha, are on a road trip to Yosemite. Ed wants Subway, I want. In-N-Out Burger, Doris wants Sonic. In the end, we compromise on McDonald's, where Alisha will get an action figure.

    It's a three-hour drive to Yosemite, but we're taking a little longer, as we're working in a tour of Highway 80's public restrooms. As the saying goes, “Not one bladder(膀胱)empties but another fills.” Many of these restrooms belong to gas stations. I prefer them to the high-tech ones on planes.

    We get back on the road. Ed is driving now. When all the tabloids(小报)have been read, the travel has grown tedious and anyone under age 12 asks “Are we there yet?” at ever-shortening internals. Just outside Manteca, California, we stop for coffee. At a Starbucks checkout, Ed buys a CD of Joni Mitchell's favorite musical picks. The hope is that it will have a calming effect.

    As we pull back onto the highway, it starts to pour. Then something amazing happens. As we climb the mountain, the rain turns to snow. The pines are spotted with white. We're struck dumb(说不出话)by the scene outside. For a solid 15 minutes, everyone forgets about their bladder, their blood sugar and the temperature. Alisha has never seen snow, so we pull over to make snowmen and catch snowflakes on our tongues. Then Ed realizes we need tire chains, and we have to turn back and drive 30miles to Oakhurst. “Good,” says Doris. “There was a very nice restroom there.”