Page 1 - 5-Lesson notes-Disease causing microorganisms in animals and plants Food poisioning
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SAI International School

                                             Subject- Biology, Class-VIII
                                      Topic- Microorganisms: Friend and Foe
                    Subtopic- Disease causing microorganisms in Animals and Plants, Food
                                                       Poisoning
                                                     Lesson Notes


               Disease causing microorganisms in Animals


                   •  Cause diseases in domestic and farm animals.
                   •  Example:
                          ❖  Anthrax (caused by Bacillus anthracis) in cattle
                          ❖  Foot and Mouth Disease in animals (viral)

               Disease causing microorganisms in  Plants


                   •  Affect crops like wheat, rice, potato, sugarcane etc.
                   •  Examples:
                          ❖  Rust of wheat (fungus)
                          ❖  Citrus canker (bacterial disease spread by air)
                          ❖  Late blight of potato (fungal infection, caused Irish famine)




                   •  Food poisoning:
                        When microorganisms grow on food, they produce toxic substances and the food
                       becomes poisonous. This is called food poisoning. Consumption of such food leads to

                       serious illness and even death.


               Robert  Koch  discovered  a  bacterium  called  Bacillus  anthracis  which  causes  respiratory
               disease anthrax in humans and animals.
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