Students get through the TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare which is useful for their exam preparation.

TN State Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

Very short answer questions

Question 1.
Name any two bacteria involved in bioremediation.
Answer:

  1. Nitrosomonas europeae
  2. Ideonella sakaiensis

Question 2.
Define mycorrhiza.
Answer:
Mycorrhiza is defined as a symbiotic association between a fungus and the roots of plants.

TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

Question 3.
Mention any two insect biopesticides.
Answer:

  1. The ladybird beetle.
  2. Dragonfly

Question 4.
Explain the Yamuna Action plan.
Answer:
The government of India and Japan are involved in this project, which was formally launched in April 1993. The proposal of building a large number of sewage treatment plants along the banks of Yamuna River to treat raw sewage and to release only treated effluent into the river is agreed upon in this project.

Question 5.
What are methanogens?
Answer:
Methanogens are methane-producing bacteria. Eg: Methanol bacterium.

Question 6.
Define organic farming.
Answer:
Organic farming is a technique, in which the cultivation of plants and rearing of animals takes place in a natural way.

Question 7.
Define Bioremediation.
Answer:
Bioremediation is defined as a process in which naturally occurring or genetically modified microorganisms are used to reduce or degrade pollutants.

TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

Question 8.
What is mycoherbicide?
Answer:
Mycoherbicide is a bioherbicide developed in 1981. It is derived from the fungus, Phytophthora palmivora. It controls the growth of strangler vine in citrus crops.

Question 9.
UV irradiation is an ideal disinfectant for wastewater why?
Answer:
UV irradiation is an ideal disinfectant for wastewater because ft does not alter the water quality except for inactivating microorganisms.

Question 10.
Name any two industrial processes in which microbes are involved.
Answer:

  1. Fermented beverages
  2. Antibiotic production.

Short answer questions

Question 1.
What is Biofuel? Explain.
Answer:
Biofuel is a fuel made from vegetable oils, fats, or greases. Biofuel can be used in diesel engines without altering the engine. The qualities of biodiesel include nontoxic, biodegradable, and production of low level of air pollutants than petroleum-based diesel fuel. The plants identified for biofuel production are Jatropha curcas and Pongamia sp.

TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

Question 2.
Mention any three genetically engineered microorganisms and their functions.
Answer:

  1. Genetically modified E.coli – Human insulin.
  2. Pseudomonas putida – Bioremediation.
  3. Genetically engineered streptococcus – To remove clots from the blood vessels.

Question 3.
List any three differences between chemical farming and organic farming.
Answer:

Chemical farming Organic fanning
In chemical farming chemical fertilizers and pesticides are used. In organic farming natural organic manure and bio pesticides are used.
The fertility of soil is reduced. Protecting the soil quality using organic materials.
Pesticide residues will be present in the produce. Since bio pesticides are used, no pesticides residue in the produce.

Question 4.
Mention any three examples of biofertilizers.
Answer:
The main sources of biofertilizers are bacteria, fungi, and cyanobacteria.

  1. Rhizobium is symbiotic nitrogen-fixing bacteria. It can fix atmospheric nitrogen into organic forms. They are present in the root nodules of leguminous plants.
  2. Mycorrhiza is a symbiotic association between a fungus and the roots of the plants. The fungus absorbs the phosphorous from the soil and transfers to the plant.
  3. Oscillatoria is a cyanobacterium-free living, prokaryotic organism. It can fix atmospheric nitrogen into useful forms and is used as a biofertilizer.

TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

Question 5.
How is a wine produced?
Answer:
Wine is made through a process of fermentation of grape juice. Saccharomyces cerevisiae is responsible for the fermentation of grape juice into alcohol. Red wine and white wine are the two types of wines available. The black grapes along with skin ‘ and even stem are used for making red wine. The juice of either white or black grapes without their skin and stem is used for the preparation of white wine.

Long answer questions

Question 1.
Explain the role of microbes in biogas production.
Answer:
Biogas is a mixture of different gases like methane (63%) with CO2 and hydrogen. The agricultural wastes, manure, municipal wastes, plant materials, sewage sludge, food waste, etc., form the raw materials for the production of biogas. In biogas production, the organics is converted into gas and organic fertilizer by microbes under anaerobic conditions.
Methanogens are methane-producing bacteria, responsible for biogas production. Methanobacterium is the common bacteria used for the production of biogas, which bums with a blue flame. The bacteria are present in the anaerobic sludge and rumen of the cattle.
The excreta of cattle is called ‘Gobar’, which forms the inoculum of the anaerobic process in the biogas unit. The biogas/ gobar gas is also generated by the anaerobic decomposition of cattle dung, by the methanogenic bacteria.

Question 2.
Draw the schematic diagram of the action of the toxin.
Answer:
TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare 8

TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

Question 3.
How is industrial alcohol produced?
Answer:
Industrial alcohol is the ethanol (C2H5OH), produced in a large scale, using the yeast, Saccharomyces cerevisiae. It is used for industrial, laboratory and fuel purposes Bacteria such as Zymomonas mobilis and Sarcina ventricuta are also used in the industrial production of alcohol.
Molasses, com, potatoes, and wood waste are the raw materials for the commercial production of industrial alcohol. During this process, the milling of feedstock, followed by the addition of dilute or fungal amylase from Aspergillus makes the drawing material break down the starch into fermentable sugar. Yeast is then added to convert the sugars into ethanol. The concentration of alcohol in the brewing is 96%, which is distilled to obtain ethanol. Ethanol is used as biofuel an alternative or additive of gasoline.

Question 4.
Draw and label the schematic diagram of the sewage treatment process.
Answer:
TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare 9

TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

Choose the correct answers:

1. Match the following:
TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare 3
(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

2. Match the following:
TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare 4
(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(iii); (q)-(iv); (r)-(i); fs)-(ii)
(d) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
Answer:
(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)

3. Match the following:
TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare 10
(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(b) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(d) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

4. The queen of drugs is:
(a) Streptomycin
(b) Chloromycin
(c) Kanamycin
(d) Penicillin
Answer:
(d) Penicillin

5. Which one is not an antibiotic?
(a) Erythromycin
(b) Cyclosporin A
(c) Bacitracin
(d) Neomycin
Answer:
(b) Cyclosporin A

6. The study of wine and winemaking is known as
(a) Zymology
(b) Homology
(c) Oenology
(d) Ornithology.
Answer:
(c) Oenology

7. Choose the odd man out:
(a) Zymomonas mobilis
(b) Sarcina ventriculi
(c) Saccharomyces cerevisiae
(d) Clostridium butyricum
Answer:
(d) Clostridium butyricum

8. Identify the odd one out:
(a) Yogurt
(b) Paneer
(c) Bread
(d) Cheese
Answer:
(c) Bread

TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

9. Find the odd one out:
(a) Ladybird beetle
(b) Dragonfly
(c) Trichoderma
(d) E.coli
Answer:
(d) E.coli

10. Which of the following is the correct pair?
TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare 5
Answer:
(b)

11. Which of the following is the incorrect pair?
TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare 6
Answer:
(c)

12. Which of the following is the incorrect pair?
TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare 7
Answer:
(a)

13. Assertion: Microbian fuel cells work by allowing bacteria to oxidize or reduce organic molecules.
Reason: Bacterial respiration is basically on big redox reaction in which electrons are being moved around.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is wrong.
(d) Both Assertion and Reason are wrong.
Answer:
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

14. Assertion: Biogas is produced by the breakdown of organic matter under anaerobic conditions.
Reason: The breakdown of raw organic waste is carried out by anaerobic bacteria.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is wrong.
(d) Both Assertion and Reason are wrong.
Answer:
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.

15. Assertion: The Biological Oxygen Demand (BOD) is high in raw sewage.
Reason: The greater the BOD in wastewater, the lesser is its polluting potential.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is wrong.
(d) Both Assertion and Reason are wrong.
Answer:
(c) Assertion is correct, Reason is wrong.

16. Which of the following is a correct statement?
(a) The sewage contains a large amount of organic matter and fewer of microbes.
(b) The sewage contains a large amount of organic matter and microbes.
(c) The sewage contains less amount of organic matter and a large amount of microbes.
(d) None of the above.
Answer:
(b) The sewage contains a large amount of organic matter and microbes.

17. Choose the incorrect statement:
(a) Cheese is a dairy product produced by coagulation of milk protein, casein
(b) The enzyme rennet is used for the coagulation of milk protein.
(c) Most cheeses is made with a starter bacteria Lactococcus.
(d) All the above statements are not correct.
Answer:
(d) All the above statements are not correct.

TN Board 12th Bio Zoology Important Questions Chapter 8 Microbes in Human Welfare

18. Indicate the correct statement:
(a) Aerobic microbes degrade the pollutants in the absence of oxygen.
(b) Pseudomonas putida is a genetically modified microorganism.
(c) It is multiplasmid organic matter degrading bacterium.
(d) It can digest the nitrogenous materials in the soil.
Answer:
(b) Pseudomonas putida is a genetically modified microorganism.