. Outlines of botany for the high school laboratory and classroom (based on Gray's Lessons in botany) Prepared at the request of the Botanical Dept. of Harvard University. Botany; Botany. STUBIES OF TJIK LEAF G7 the weight, leave plant couiiteilialanced on tlie scales. In a relatively short time it will be seen whether tlie plant gains or loses. Set the plant in a sunny or well-lighted place. If possible weigh again some liours later the same da}'; if not, the next day. Kecord weight and time. Let tlie plant now remain in darkness as nearly as [lossible an eqnal length of time. Again wei
. Outlines of botany for the high school laboratory and classroom (based on Gray's Lessons in botany) Prepared at the request of the Botanical Dept. of Harvard University. Botany; Botany. STUBIES OF TJIK LEAF G7 the weight, leave plant couiiteilialanced on tlie scales. In a relatively short time it will be seen whether tlie plant gains or loses. Set the plant in a sunny or well-lighted place. If possible weigh again some liours later the same da}'; if not, the next day. Kecord weight and time. Let tlie plant now remain in darkness as nearly as [lossible an eqnal length of time. Again weigh, and record weight and time. AVhat has caused the change; of weight? (Befoie the answer is re- quired, tlie next experiment will naturally have been done; there will be additional reason to assign the change of weight to one particular cause.) What effect has light upon the rate of change? Experiment 14.^ — Two tumblers, a piece of pasteboard, a piece of sheet rubber large enough to cover the mouth of the tumbler, and a leaf, are needed. One tumbler is nearly tilled with water. The paste- board, with a hole in it, is placed on this tumbler. A puncture is made in the middle of the rubber, the rubber stretched, and the leaf- stalk put through the puncture. The leaf is now put on the tumbler, its stalk descends into the water through the hole in the pasteboard. The blade of the leaf is now covered with the second tumbler, and the apparatus set in the sun. In a few minutes an effect, ilue to the activity of the leaf under the influence of light and lieat, should be seen. Experiment 15. — Relative activity of the upper and under sides of the Begonia leaf.— a^. Two dry watch glasses are to be placed on oppo- site sides of a Begonia leaf (still on the plant) and held in place liy a cliji, or bj' two wooden strips and elastic bands, as in the figure. Two inclosed spaces are thus made, on the ruider and upper faces of the leaf respectively. Neither should be in direct sunlight.
Size: 985px × 2537px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectbotany, bookyear1901
