52 OCCURRENCE OF PATHOGENIC BACTERIA IN NATURE 



5. Name a pathogenic bacterium which generally finds entrance by one 

 definite route only. 



6. Name some pathogenic bacteria which may find entrance through several 

 routes. 



7. How does the intact skin act toward pathogenic microorganisms? How 

 mucous membranes? 



8. Name some pathogenic bacteria which generally gain entrance into the 

 body of an animal through wounds. 



9. Can animals be infected through the intact skin or mucosa, and if so, by 

 what microorganisms? 



10. How does granulation tissue act toward pathogenic bacteria? 



11. How does the nasal mucosa act toward pathogenic microorganisms? 



12. How do the pharyngeal tonsils act in the same respect? 



13. Name some microorganisms invading the body through the gastro-intes- 

 tinal tract. 



14. At what point of the gastro-intestinal tract may they enter into the 

 tissues? 



15. Name a disease common in cattle which generally makes its entrance 

 through the mucosa of the mouth. 



16. Name some diseases in animals generally contracted through sexual 

 intercourse. 



17. How can a bull transfer the bacillus of infectious abortion to a cow? 



18. Do pathogenic microorganisms always produce their most important 

 lesions at their place of entrance? If not, what may happen? 



19. What is meant by a cryptogenetic infection or an infection of crypto- 

 genetic origin? 



20. What is meant by a latent infection? 



21. What is meant by auto-infection? 



22. Name a bacillus which ordinarily lives in the intestines of man and animals 

 as a harmless commensale, but which may produce auto-infections. 



23. How can bacteria enter the embryo through the fetal circulation? 



24. Name some insects and allied animals which as intermediary hosts may 

 spread infectious diseases. 



25. How and where are pathogenic bacteria excreted? 



26. How can tubercle bacilli from the lungs be excreted with the feces? 



27. Name some diseases of cattle in which the pathogenic bacteria are voided 

 with the urine or vaginal secretion. 



