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and is not uniform throughout ; the inner mass (the endo- 

 plasm or endosarc) is coarsely granular and more opaque 

 than the outer film (the ectoplasm or ectosarc) which is 

 finely granular, clearer, and of a firmer consistency. The 

 granules are mostly food reserves and waste materials. 

 Grains of sand, globules of fat, green vegetable organisms, 

 and other conspicuous foreign bodies are often present 

 in the endoplasm. Some of these are surrounded by fluid, 

 and are termed food-vacuoles. A large, rounded, solid- 

 looking body, more or less visible in the endoplasm, is the 

 nucleus. Near the ectoplasm an opening, the contractile 

 vacuole, appears at intervals ; at first very small, it rapidly 

 expands into a large, clear sphere, and then suddenly 

 vanishes. 



How would you explain the Change of Shape ? 



The cell or body of the Amoeba is naked ; there is no 

 rigid or limiting wall. Localised changes in the tension 

 of the elastic outer film may partly explain the outflowings 

 of the protoplasm which cause the irregularity of form. 



How does the, Amoeba move ? 



Slowly by blunt outflowings or outpushings of the proto- 

 plasm called lobopods or pseudopodia. As the pseudopodia 

 flow out, a slime is secreted without which progression 

 would be impossible. 



What is the Function of a Contractile Vacuole ? 



It is apparently a sort of drain in which the finer wastes 

 of the protoplasm are collected. Its formation is sirpposed 

 to be due to a constituent substance of the protoplasm 

 that has a strong affinity for water. The effete fluid 

 gathers into a droplet which, as it swells, is moved to the 

 surface, and there suddenly expelled by contraction. 



How does the Amoeba feed ? State what you know about the 

 Process of Digestion. 



When it moves near to a diatom or other edible object, 

 it protrudes pseudopodia. These flow out until they 



