. Laboratory problems in civic biology. Biology. PROBLEM 56 75 l|>«=-i{ H Find little cores of wood extending out through the cortex into the rootlets. This so-called central cylinder is made up of bundles of tubeUke cells. The cells collectively form the fibrovascular bundles. In the picture of the cross section (see page 74, Civic Biology) find (1) the cortex, (2) the central cylinder, and (3) the root hairs. How many cells are in a root hair ? From what part of the root do the root hairs grow? Place some bean or corn seedlings in red ink. Allow them to remain in the sun for a few hours a
. Laboratory problems in civic biology. Biology. PROBLEM 56 75 l|>«=-i{ H Find little cores of wood extending out through the cortex into the rootlets. This so-called central cylinder is made up of bundles of tubeUke cells. The cells collectively form the fibrovascular bundles. In the picture of the cross section (see page 74, Civic Biology) find (1) the cortex, (2) the central cylinder, and (3) the root hairs. How many cells are in a root hair ? From what part of the root do the root hairs grow? Place some bean or corn seedlings in red ink. Allow them to remain in the sun for a few hours and then examine the stem and leaves carefully. What has happened? Cut a cross section of one of the above stems. Which part of the root and stem shows the pres- ence of red ink? Examine free-hand sections under the microscope. Conclusion. — By what path do fluids pass up the root and stem? Problem 56: To find out how root hairs absorb soil water. Materials.—Egg or glass test tube (large), celloidin, seaUng wax, glass tubing, thistle tube. Method. — To make an artificial root hair we may take either an egg, or a celloidin cell, which is made by pouring a little thin celloidin into a clean test tube, revolving the tube rapidly, and then carefully removing the film of celloidin which has been formed within the tube. With care a nearly uniform artificial membrane will have been formed within the tube. This, when removed, may be filled with glucose solution, or any dense material that will dissolve in water. Tie the upper end of it tightly over the wide end of a thistle tube and insert the bag in a dish of water. If an egg is to be used, break the shell at one end and remove. Apparatus to show Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Hunter, George William, 1873-1948. New York, Cincinnati
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbiology, bookyear1916
