138 DIVISION OF LABOR 



a. Algae 



Method and Observations. — Examine some pond scum with a 

 hand lens. What kind of body has the plant ? Has it any root, 

 stem, and leaves? Look at specimens under the microscope and 

 on the chart to determine the methods of reproduction. 



Conclusion. — 1. Would such a plant as this have much division 

 of labor ? Many different organs ? 



2. How does such a plant reproduce ? 



b. Fungi 



Method and Observations. — You have already studied a yeast 

 and a mold as examples of fungi. Study in addition a shelf fungus. 

 Remember that the shelf-like part is the reproductive portion 

 (much like the sporangium and stalk of black mold). Study a 

 piece of decayed wood containing mycelium of bracket fungus. 

 What is its general appearance ? Compare with mycelium of mold. 



Conclusion. — Is division of labor greater in the algae studied 

 or in the fungi studied ? Explain fully. 



c. Mosses 



Method and Observations. — Notice that the body of the moss 

 shows rootlike structures, rhizoids; an upright stem; and leaf- 

 like structures. Notice that some bear stalks with a little capsule 

 on the top. The stalk and capsule bear asexual spores and are 

 known as the asexual generation. The moss plants produce egg 

 and sperm cells in different organs, giving the title of sexual 

 generation to this part of the plant. 



Conclusion. — Does the separating of the plant into two phases, 

 a sexual and an asexual phase, result in greater or less division of 

 labor? Explain. 



d. Ferns 



Method and Observations. — The fern plant has roots, an 

 underground stem, and large leaves called fronds. On the backs 

 of some of the fronds are found asexual spore-producing bodies, 

 sporangia. The sexual part of the fern (see chart) is a very tiny 

 body called a prothallus. 



