Tag: environmental use of microorganism

Questions Related to environmental use of microorganism

Select the correct statement from the following.

  1. Methanobacterium is an aerobic bacterium found in rumen of cattle.

  2. Biogas commonly called gobar gas is pure methane.

  3. Activated sludge sediment in settlement tanks of sewage treatment plant is a rich source of aerobic bacteria.

  4. Biogas is produced by the activity of aerobic bacteria on animal waste.


Correct Option: C
Explanation:
Methanobacterium is an anaerobic bacterium..
Biogas is a mixture of gases (predominantly methane).
Biogas is produced by the activity of anaerobic bacteria.
Correct answer-C

Identify the correct sequence of steps involved in the treatment of sewage.
(i)   Growth of aerobic microbes to reduce BOD
(ii)  Sequential filtration for removing floating debris
(iii) Production of inflammable gas
(iv) Growth of anaerobic microbes for digestion of bacteria

  1. i, iv, ii, iii

  2. ii, iv, i, iii

  3. ii, i, iv, iii

  4. iv, ii, iii, i


Correct Option: C

The primary treatment of sewage water involves.

  1. Sludge digestion

  2. Aerobic bacterial activity

  3. Anaerobic bacterial activity

  4. Filtration and sedimentation


Correct Option: D

Sewage water is purified by

  1. Microorganisms

  2. Light

  3. Fishes

  4. Aquatic plants


Correct Option: A
Explanation:

Sewage is composed of organic matter and domestic waste. The pollutants are removed by the sewage treatment process to mitigate it's adverse impact on the environment when it is released. The sewage pass through primary,  secondary and tertiary treatment. The microorganisms by aerobic and anaerobic metabolism degrade the organic matter in secondary and tertiary treatment respectively making it disinfected.

Hence, the correct answer is 'Microorganisms'.

Which one is a biological in sewage treatment?

  1. Primary treatment

  2. Secondary treatment

  3. Tertiary treatment

  4. All of the above


Correct Option: B
Explanation:

The sewage treatment unit employs the primary, secondary and tertiary treatment for the complete process. In the primary treatment, filtration of the large and solid waste is done. Then in secondary treatment, the decomposing microbes are used for the breakdown of the organic sewage. So, the secondary treatment is the biological treatment of the waste water. In the tertiary treatment, the chemical treatment is provided to the water.

Hence, the correct answer is 'Secondary treatment'

Sewage sludge is used as a

  1. Manure

  2. Biogas generator

  3. Tipping

  4. Both A and B


Correct Option: D
Explanation:

Sewage sludge is a product of wastewater treatment. Once treated, sewage sludge is then dried and added to a landfill, applied to agricultural cropland as fertilizer, or bagged with other materials and marketed as “bio-solid compost” for use in agriculture and landscaping.

Hence, the correct answer should be 'Both A and B'.

Chlorination of treated waste water is required for

  1. Killing all microbes

  2. Removing suspended materials

  3. Complete breakdown of organic matter

  4. All of the above


Correct Option: A
Explanation:

Chlorination is the process of treating the water with chlorine to kill the water-borne microbes that can possibly cause diarrhoea, typhoid, jaundice, amoebiasis etc. It is performed during the tertiary treatment step. Chlorine compounds like sodium hypochlorite are added to water to give effect to the process.

A. Chlorination kills the microbes.
B. Suspended particles are removed by filtration.
C. The complete breakdown of organic matter occurs by decomposition during the secondary treatment.
Hence, the correct answer is 'Killing all microbes'

In treatment of waste, biological treatment is

  1. Primary treatment

  2. Secondary treatment

  3. Tertiary treatment

  4. Reverse osmosis stage


Correct Option: B
Explanation:

The sewage treatment unit employs the primary, secondary and tertiary treatment for the complete process. In the primary treatment, filtration of the large and solid waste is done. Then in secondary treatment, the decomposing microbes are used for the breakdown of the organic sewage. So, the secondary treatment is the biological treatment of the waste water. In the tertiary treatment, the chemical treatment is provided to the water.

Hence, the correct answer is 'Secondary treatment'

Sewage treatment in which a portion of decomposer bacteria present in waste is recycled into the beginning of the process is

  1. Cyclic treatment

  2. Activated sludge treatment

  3. Primary treatment

  4. Tertiary treatment


Correct Option: B
Explanation:

Activated sludge treatment is the step involved in the treatment of sewage water. The sewage is treated in a large aerated tank and bacteria. Once, the process of decomposition is over, the filtrate obtained is called the activated sludge because it contains a high number of bacteria. This is then recycled in the next slot of treatment when the polluted sewage is available for the treatment. The activated sludge speeds up the process of decomposition by acting as an inoculum in the aeration tank. Primary treatment is the removal of large solid particles from the sewage. Tertiary treatment involves chemical treatment of the sewage water.

Hence, the correct answer is 'Activated Sludge treatment'.

The residue left after methane production from cattle dung is:

  1. burnt

  2. burned in land fills

  3. used as manure

  4. used In, civil construction


Correct Option: C
Explanation:
The residue left after methane production from cattle dung is used as manure because it supply some organic materials and minerals to the soil.
So, the correct answer is 'used as manure'