REPRESENTATIVE TEST 

 QUESTIONS FOR STUDENTS 



1. Define a cell and a tissue. [A cell is a unit corpuscle or area of 

 living matter, usually centred in a nucleus. A tissue is an aggregate of 

 similar cells performing similar functions, e.g. a piece of muscle, a piece 

 of brain, a piece of gristle, a piece of bone. Blood is a fluid tissue.] 



2. Make a diagram showing the life-history of an amoeba. [Growth, 

 limit of growth, multiplication by division, encystment in drought, 

 rejuvenescence, occasional spore-formation and conjugation.] 



3. Distinguish the different kinds of death, [(a) Violent, due to some 

 serious breakage or lesion of an important part, or to smothering, 

 poisoning, drowning, etc. (b) Microbic or parasitic, due to the invasion 

 of the body by intruding organisms which break down tissues, block 

 passages, produce poisons, etc. (c) Natural, due to the mounting-up of 

 unrecuperated wear-and-tear results, especially in the more stable 

 framework of the cells, processes of rejuvenescence failing to com- 

 pensate for processes of senescence.] 



4. Why is it that Protozoa are not subject to natural death in the same 

 degree as higher animals are ? [They have no " body " to keep up, 

 processes of rejuvenescence can thus more readily keep pace with 

 processes of senescence. The modes of reproduction are on the whole 

 less expensive physiologically than they are in Metazoa.] 



5. How do Protozoa multiply ? [Mainly by fission, budding, and 

 spore-formation. ] 



6. Give an illustrated account of the life-history of Paramcccium. 



7. What is symbiosis ? Give examples. [A mutually beneficial 

 internal partnership between two organisms of different kinds ; usually 

 unicellular plants within animals, e.g. the symbiotic Algse in Radio- 

 larians. Hydra viridis, some sea-anemones, ^Convoluia, etc. ; sometimes 

 plant within plant, e.g. lichens.] 



8. Mention several Protozoa that directly injure man, stating what 

 the injury is. [Trypanosome causing sleeping sickness, Plasmodium 

 causing malaria, Entamoeba histolytica causing abscesses of the liver.] 



9. What are phagocytes and what do they do ? [Wandering amoeboid 

 cells found in all Metazoa except nematodes and lancelets, which 

 transport nutritive material from one part to another, engulf and 

 digest intruding microbes, surround irritant particles, are active in all 

 processes of inflammation, assist like sappers and miners in meta- 

 morphosis, degenerative and reconstructive changes, etc. In higher 



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