QUESTIONS, PROBLEMS, AND SUGGESTIONS 

 For Study, Review, or Examination 



An animal is a living, organized being with living protoplasm as the 

 essential foundation or "The Physical Basis of Life." An animal, whether 

 an ameha or a bird, is more marvelous than any machine man ever invented. 

 The animal has the powers of nutrition {i. e. is auto- or self-feeding), excre- 

 tion (self-waste eliminating), self-metabolism (power to change substances 

 into others of different chemical composition), irritability (response to 

 stimuli), contractility (ability to move itself), sensitivity and special senses 

 (by means of which it discovers itself and its environment), and self-repro- 

 duction. It has self-defense and automatic (self) response or rmvement. 



The more you study and observe animals, the more marvelous and inter- 

 esting they become until you enter into the spirit of nature study. Then 

 you have a lifetime of enjoyment, pleasure, and profit ahead of you. En- 

 rich your life. Get this spirit and sympathy with animal life, as John Bur- 

 roughs and many other naturalists have done, and thus greatly enlarge 

 your life's horizon. 



PROTOZOA 



1. The body of protozoans consists of one cell, as in Ameba, or a colony 

 of cells, as in Gonium. How can one cell do all that is essential to an 

 animal's existence — -in nutrition, growth, reproduction, locomotion, de- 

 fense, and sensitivity or irritabilitj^? 



2. The symmetry of the animal body is: (1) asymmetric, as in the Ameba; 

 (2) radial, as in the starfish; or (3) bilateral, as in most of the animal king- 

 dom. How does the symmetry of the body affect its locomotion? What 

 kind of motion has an asymmetric animal, e. g., the Ameba? One of 

 radial symmetry, as the starfish? One of bilateral symmetry, as the bird? 



3. What are the means and manner of locomotion, nutrition, reproduc- 

 tion, behavior, and defense of Protozoa? 



4. The struggle for existence is threefold: (1) with their own kind; (2) 

 with different kinds; (3) with their fivefold environment. Which do you 

 consider the most severe, and why? 



.5. Environment is fivefold: (1) organic or life; (2) atmospheric; (3) 

 u(!ue(;us (water in its various forms); (4) igneous or heat; and (5) terranean 

 (the solid earth) . Which one of this fivefold invironment affects protozoans 

 most in their struggle for existence? 

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