Microorganisms friends and foe Worksheet-15

Microorganisms friends and foe Worksheet-15


Comprehension-Based Questions:

Microorganisms are classified into four major groups. These groups are bacteria, fungi, protozoa and some algae. Viruses are also microscopic. They, however, reproduce only inside the cells of the host organism, which may be a bacterium, plant or animal. Common ailments like cold, influenza (flu) and most coughs are caused by viruses. Serious diseases like polio and chicken pox are also caused by viruses. Diseases like dysentery and malaria are caused by protozoans. Typhoid and tuberculosis (TB) are bacterial diseases. Microorganisms are used for various purposes. They are used in the preparation of curd, bread and cake. They are also used in cleaning up of the environment. In agriculture they are used to increase soil fertility by fixing nitrogen.

  1. In how many groups microorganisms are classified?

(A) Two              (B) Three           (C) Four             (D) Five


  1. Amoeba belongs to _____ group.

(A) Bacteria      (B) Protozoa     (C) Fungi           (D) Algae

(E) Virus


  1. Which of the following is connecting link between living and non-living?

(A) Bacteria      (B) Protozoa     (C) Fungi           (D) Virus

(E) Algae


  1. Chicken-pox is ______ disease.

(A) Bacterial     (B) Protozoan   (C) Viral             (D) Fungal


  1. Which of the following can behave as host for virus?

(A) Bacteria                                   (B) Plant cell

(C) Animal cell                              (D) All


  1. Which of the following disease caused by Entamoeba.

(A) Flu                (B) Typhoid       (C) Dysentery   (D) Malaria


  1. Microorganism improve soil quality by-

(A) Fixation of carbon dioxide  (B) Fixation of nitrogen

(C) Fixation of oxygen                 (D) All


  1. Preparation of curd, cakes, alcohol and pastries involved _____.

(A) Protozoans (B) Viruses        (C) Bacteria      (D) All


Answer in a word:

  1. Name one deadly disease of 20th century  caused by virus

  2. What is abbreviation of TB?

  3. Name the organism that remains inactive outside the living cell.

  4. Name the pathogen of malaria.

  5. Name the bacteria causes curdling of milk.

  6. Name the group of microorganism that lives in colony.

  7. Which is called Brewer’s fungus?

  8. Name the organism responsible for commercial production of alcohol.

  9. What is called the process of conversion of sugar into alcohol?

  10. What is called the medicines used to kill microorganism?

  11. Is penicillin is an antibiotic?

  12. What is called the disease causing microorganism?

  13. Give the name of carrier of malaria.

  14. What is called the process of boiling milk to make it free from bacteria?

  15. Name the microorganism that lives in root nodules of leguminous plants in symbiotic relationship.



  1. Four

  2. Protozoa

  3. Virus

  4. Viral

  5. All

  6. Dysentery

  7. Fixation of nitrogen

  8. Bacteria

  9. AIDS

  10. Tuberculosis

  11. Virus

  12. Plasmodium

  13. Lactobacillus

  14. Algae and fungi

  15. Yeast

  16. Yeast

  17. Fermentation

  18. Antibiotics

  19. Yes

  20. Pathogen

  21. Female Anopheles mosquito

  22. Pasteurization

  23. Rhizobium