GLOSSARY 



Bacteria are microscopic one-celled plants, which may Hve as individuals 

 or in groups called colonies, and which reproduce mainly by cell 

 division. 



The cambium is a cylinder in the plant just inside the true bark made of 

 a single layer of cells which can divide to add cells to the bark on its 

 outside and to the wood on its inside. It supplies the cells for the 

 growth in thickness. 



Chlorophyll is the complex chemical green pigment of plants. 



A chloroplast is a small amount of specialized protoplasm which contains 

 chlorophyll. 



Chrom,atin is a protein compound found in the nucleus of a cell, which 

 determines the characteristics of the organism. 



ChromosoTTie is a short thread-like structural unit of chromatin visible 

 during the division of the cell. 



A clone is a group of plants vegetatively propagated from the same 

 parent. 



The coleoptile is a tube or sheath covering the plumule of the grass-type 

 seedling until it emerges from the soil, after which the coleoptile 

 dies. 



A corm is a shortened fleshy stem with leaves growing frOm the upper 

 side and roots from the lower side, as in gladiolus. 



The cortex is a group of thin-walled cells inside the epidermis with a 

 variable function, but most frequently it stores food and in many 

 cases has chlorophyll, hence it makes food. 



Cross-pollination is the transfer of pollen from the anther of a flower to 

 the stigma of a flower on another plant. 



Cytology is the study of the internal structure of the cell, i.e., with chro- 

 mosomes. 



The cytoplasm is the living matter of a cell outside the nucleus. The 

 nucleus and cytoplasm constitute the protoplasm of a cell. 



Diffusion is the spontaneous intermingling of the molecules of two (or 

 more) liquids or gases in combination, which results in an equal 

 distribution of the molecules of each liquid or gas among those of 

 the other. Diff"usion is caused by the characteristic of all ions or 

 molecules to go from regions of their respective greater concen- 

 trations. 



A dicotyledonous plant is one which produces seeds with two seed leaves 

 (cotyledons) such as the two fleshy bodies in a pea or bean seed. 



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