Chapter 7 The Microbial World VSAQs
Question 1. What are microbes?
Answer:
Microbes:
Microscopic living organisms other than plants and animals.
Question 2. What is the whitish layer, formed on the surface of bread during the rainy season?
Answer:
It is a layer of fungus.
WBBSE Class 8 Quick Answers on Microbes
Question 3. What are the most primitive and ancient organisms found on earth?
Answer:
Microbes are the most primitive and ancient organisms.
Question 4. Name one anaerobic microbe.
Answer:
Yeast (or tetanus-causing pathogen) is an anaerobic microbe.
Question 5. What is the term used to denote the organisms living on dead and decaying organic matter?
Answer:
They are called saprotrophs.
WBBSE Class 8 Very Short Answer Questions Microbial World
Question 6. Which microbes can produce their own food?
Answer:
Algae can produce their own food.
Question 7. What are thermophilic bacteria?
Answer:
Thermophilic Bacteria:
They can grow and survive even at about 100X.
Question 8. What types of bacteria are found in hot springs?
Answer:
Types of bacteria are found in hot springs:
Thermophilic bacteria are found in hot springs.
Question 9. What is staining?
Answer:
Staining:
It is the process of coloring specimens for identification under a microscope.
Question 10. Which cell organelle is present in bacteria?
Answer:
Ribosomes are present in bacteria.
Read And Learn More WBBSE Solutions For Class 8 School Science Very Short Answer Type Questions
Question 11. State the characteristics of bacterial DNA.
Answer:
It is circular DNA, not enclosed within the nucleus.
Question 12. Name a locomotory structure of protozoa, other than pseudopodia.
Answer:
The locomotory structures may be cilia or flagella.
Chapter 7 The Microbial World WBBSE Answers
Question 13. What are the units of fungal mycelium?
Answer:
Units of fungal mycelium:
A large number of hyphae form mycelium
Question 14. Give an example of a unicellular roundish fungus.
Answer:
Yeast is a unicellular, roundish fungus.
Question 15. Why fungi can not synthesize their own food?
Answer:
Because they do not have chloroplasts in their cell.
Question 16. Name colonial algae.
Answer:
Colonial algae:
Volvox is a colonial alga.
Question 17. Why algae can synthesize their own food (autotrophic)?
Answer:
Because they have chloroplasts in their cytoplasm.
Question 18. Which microbes cause smallpox?
Answer:
Smallpox is caused by a virus.
Question 19. Which microorganisms do not have a nucleus and cytoplasm?
Answer:
Viruses do not have a nucleus and cytoplasm.
WBBSE Class 8 Science Very Short Answer Format
Question 20. What type of nucleic acid is found in viruses?
Answer:
The nucleic acid is either DNA or RNA.
Question 21. Which microbes show the characteristic of living only within the body of a host?
Answer:
Viruses behave like living only within the body of a host.
Question 22. Which type of microbes causes amoebiasis?
Answer:
Some protozoal microbes are responsible.
Question 23. How tuberculosis can spread from one person to other?
Answer:
It can spread through cough and sneezing.
Question 24. Which symbiotic bacteria are found in root nodules of leguminous plants?
Answer:
Rhizobium lives in root nodules.
Question 25. Which symbiotic bacteria live in the human intestine?
Answer:
The symbiotic bacteria Escherichia coli live in the human intestine.
Question 26. Which microbial association is found in Lichen?
Answer:
In lichen, an association of algae and fungi is found.
Question 27. What is the term used to denote the mutually beneficial association between two organisms?
Answer:
The term is symbiosis.
Question 28. How the bacteria Azotobacter is helpful?
Answer:
It helps to fix nitrogen in the soil.
WBBSE Class 8 Science Important Very Short Answers
Question 29. What is the function of nitrifying bacteria?
Answer:
It converts ammonia into nitrate and nitrite.
Question 30. Which bacteria help in the formation of curd from milk?
Answer:
The bacteria is Lactobacillus.
Question 31. What is the term used for the process of food preservation in air-tight containers?
Answer:
It is known as canning.
Question 32. By which process, milk can be preserved?
Answer:
It is done by Pasteurization.
Question 33. what are antibiotics?
Answer:
Antibiotics:
These are life-saving drugs produced from microbes.
Question 34. Who first discovered antibiotics?
Answer:
Alexander Flemming first discovered antibiotics in the year 1928.
Question 35. What are antigens?
Answer:
Antigens:
Antigens are foreign substances that may enter our body fluid.
Very Short Answer Questions for Class 8 Microbial World
Question 36. What are antibodies?
Answer:
Antibodies:
Antibodies are protein substances produced by our body’s defense mechanism to fight against antigens.
Question 37. What is vaccination?
Answer:
Vaccination:
Vaccination is the administration of antigenic material (a vaccine) to stimulate an individual’s immune system to develop immunity against a pathogen.
Question 38. Name two diseases that can be controlled, by vaccination.
Answer:
Typhoid, tetanus, polio, diphtheria, smallpox, tuberculosis, etc (any two are to be .. mentioned).
Question 39. Which gas may be produced from the treatment of wastes?
Answer:
Methane gas may be produced.
Question 40. Name algae that is used in space shuttles.
Answer:
Chlorella is used to clean the enclosed air.
Question 41. Name some methods of food preservation.
Answer:
Pasteurization, Pickling, Freezing, etc.
WBBSE Class 8 Science Study Guide Microbial World
Question 42. What are biofertilizers?
Answer:
Biofertilizers:
Biofertilizers are the microbes that can bring about the nutrient enrichment of soil and enhances the nutrient availability to crop plants. Example: Azotobacter, Azolla-anabaena, Rhizobium etc.
Question 43. Name two plant pathogenic fungi.
Answer:
Albugo Candida and Puccinia graminis.
Microbial World WBBSE Class 8 Resources
Question 44. Name two algae that are used as food.
Answer:
Alaria and Laminaria.
Question 45. Name a virus that is used as a biopesticide.
Answer:
Nucleopolyhedrosin virus (NPV).