SECTION II. CELL STRUCTURE AND GROWTH 



A. THE CELLULAR STRUCTURE OF PLANTS 



1. Mounting sections. Mount sections of cork, pith, or similar 



materials as follows for microscopic observation : Clean 

 a slide and cover glass as directed by an instructor. 

 With the point of your scalpel or with a small brush 

 place a section of pith or cork in the center of a glass 

 slide. Add a drop of alcohol with a pipette. Take a 

 clean cover glass with forceps, or grasp it by its edges 

 between thumb and forefinger. Place one edge of the 

 cover glass on the slide at the edge of the drop of alcohol 

 and gently lower the cover glass over a specimen. 

 This method of placing a cover glass over an object 

 avoids air bubbles, which appear under a cover glass as 

 dark rings with light centers. Now observe your section 

 with the compound microscope as indicated below. 



2. Low-power study. Place the section, mounted as directed 



above, on the stage of the microscope for observation. 

 Adjust your mirror until you have a white field, and 

 make the following observations and drawings: 



a. Compare the appearance of your section with that of a 



similar section of a honeycomb. Is it made up of 

 cells, like a honeycomb, with similar bounding walls 

 and cavities ? Compare your section with a piece of 

 honeycomb if the latter is available. 



b. Make an accurate drawing of a portion of your section 



as it appears under a low power. Label the parts 

 with appropriate terms corresponding to similar 

 structures in a honeycomb. 



