Secondary sewage treatment is mainly a
Show Hint
The microbes function to reduce the waste toxicity tested by measuring the BOD.
- physical process
- mechanical process
- chemical process
- biological process
The Correct Option is D
Solution and Explanation
The treatment of sewage is a biological process because it involves the treatment of microorganisms.
- The microbes function to reduce the waste toxicity tested by measuring the BOD (biological oxygen demand) and COD (chemical oxygen demand) value of the water.
- The microbes help to treat the sludge that is produced by the wastewater.
- Therefore, it is called a biological process.
Option A:
A physical includes gradual change through transient states. The treatment of sewage water is not a physical process.
Option B:
No objects interact to generate mechanical energy in secondary sewage treatment.
Option C:
Treatment of sewage is not a chemical process as a change in chemical state or production of different chemicals is not involved.
Therefore Option D is correct - Secondary sewage treatment is mainly a biological process.
Top Questions on Microbes in human welfare
Answer the following questions:
1. State what do you understand by “MALT”? Where is it located inside our body?
2. Explain cytokine barriers.
3. Name the diagnostic test for AIDS. On what principle does it work?
4. Bone marrow and thymus play an important role in human immune system. Explain how are they able to achieve this.- CBSE CLASS XII - 2025
- Biology
- Microbes in human welfare
Name an alcoholic drink which is produced with the help of microbes:
(1) With distillation
(2) Without distillation- CBSE CLASS XII - 2025
- Biology
- Microbes in human welfare
- Explain how cyanobacteria can be used as bio-fertilizer.
- CBSE CLASS XII - 2025
- Biology
- Microbes in human welfare
Match the items in Column-A with that of Column-B:
- CBSE CLASS XII - 2025
- Biology
- Microbes in human welfare
- Which chemical is obtained from microorganism Aspergillus niger}?
- CBSE Compartment XII - 2025
- Biology
- Microbes in human welfare
Questions Asked in AIPMT exam
- The terga, sterna and pleura of cockroach body are joined by
- AIPMT - 2015
- Cockroach
- Three identical spherical shells, each of mass m and radius r are placed as shown in figure. Consider an axis X X' which is touching to two shells and passing through diameter of third shell. Moment of inertia of the system consisting of these three spherical shells about XX' axis is
- AIPMT - 2015
- Moment Of Inertia
- The species $ {Ar, K^+}$ and $ {Ca^{2+}}$ contain the same number of electrons. In which order do their radii increase?
- AIPMT - 2015
- properties of d block elements
- The hilum is a scar on the
- AIPMT - 2015
- Post-Fertilisation : Structures And Events
- The heat of combustion of carbon to $ {CO_2}$ is $ {- 393.5 \, kJ/mol}$. The heat released upon formation of 35.2 g of $ {CO_2}$ from carbon and oxygen gas is:
- AIPMT - 2015
- Enthalpy change
Concepts Used:
Microbes in Human Welfare
There are several valuable microorganisms that are beneficial to humans in various manners such as:
In Household Products
- Fermentation of milk to produce yogurt.
- Milk cuddling to compose curd, cheese, and paneer.
In Industrial Products
- Production of beverages such as wine, beer, whiskey, brandy, or rum.
- Production of antibiotics such as Penicillin and other chemical substances to kill or retard the expansion of disease-causing microbes.
Fermented Beverages
- A fermentor is used to produce microbes on a large scale for industrial purposes.
- The brewer’s yeast (Saccharomyces cerevisiae) is used to make ethanol. At this time, the yeast ferments malted cereals and fruit juices.
Antibiotics
- The term antibiotic means “against life”. These materials can kill or destroy the growth of other microbes.