CONTENTS 



APTER PAGE 



I. THE SCOPE OF BIOLOGY . . . . . 1 

 The New Biology and the Old. The Funda- 

 mental Properties of Living Things. Chemical 

 Composition of giving Tissues. Origin of 

 Life. The Biological Sciences: Morphology. 

 Physiology. Zoology and Botany. 



II. CELLS AND THE CELL THEORY . . , . 26 

 Organisms. The Cell as the Unit of Organic 

 Structure. Cell Structure. Cell Substance or 

 Protoplasm. The Nucleus. The Centrosome. 

 The Cell Wall. Cell Functions. History of 

 the Cell Doctrine: 1. The Early Conception 

 of the Cell (1839-1861). 2. Protoplasm and 

 the Mechanical Theory (1861-1885). 3. The 

 Nucleus and its Significance (1880 to the 

 present). What is Meant by Protoplasm. 



III. UNICELLULAR ORGANISMS 52 



Animals: AmcebcL Paramedwn. Plasmo- 

 dium Malarice. Chilomonas. Pandorina. In- 

 termediate Organisms: Peranema. Euglena. 

 Plants: Pleurococcus. Saccharomyces Yeast. 

 Bacteria. 



IV. CELL MULTIPLICATION AND THE CELLULAR 



STRUCTURE OF ORGANISMS .... 85 

 Cell Division or Karyokinesis. Unicellular 

 and Multicellular Organisms. Penitillium, a 

 Simple Multicellular Plant. Other Species of 

 Molds. 



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