CHAPTER XXIV 
FUNGI —PLANTS THAT LACK CHLOROPHYLL 
273. Fungi. — The Fungi are of importance to us be¬ 
cause : (1) some can be used as food (the so-called mush¬ 
rooms) ; (2) one of them, the yeast plant, is used in making 
bread, beer, and wine; (3) others spoil our food, as when 
they grow on bread and cake ; (4) they cause many diseases 
in plants. 
Fungi differ from most other plants in two respects. 
They are colorless, or nearly so, chiefly because they have 
Figure 290 . — Yeast Plants. 
A, single cell; B, cell with buds; C, group of cells; D, chain of cells. 
no chlorophyll. They are dependent for food on plant or 
animal substances, either dead or alive, because they lack 
chlorophyll and hence cannot make their own foods as the 
green plants do. 
Fungi which live on the substances or juices of live plants 
or of animals are called parasites (Greek, para, beside ; sitos, 
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