Science MCQ (1 Marks)

It is used to disinfect water.

All of the above.

Wastewater after cleaning is returned to the sea.
Moreover, Our tap water, water in river and reservior are the sources of clean and safe water storage.

Septic tanks are underground tanks in which sewage is collected and allowed to decompose with the use of bacteria.
Drainage tanks are used to remove water. Sewage pollutes the water bodies when directly discharged into water bodies like river.
Septic canal is a tubular passageway for the disposal for sewage.

The biogas produced is used as a fuel.
The human waste or human excreta can be used in a biogas plant along with cow dung for making biogas.
So, in many villages, human excreta from the toilet seats in the homes flows directly into biogas plant through covered drains.

Waste water release by houses is called sewage.

Sewage is wastewater released by homes, industries, hospitals, offices and other users.
It also includes rainwater that has run down the street during a storm or heavy rain.
The water that washes off roads and rooftops carries harmful substances with it.

They harden and block the pipe.

Bar screening is a technique used to filter large products from the waste water.
A mechanical filter is formed in the way of waste water flow, so that the large solid wastes like rags, plastics, etc can be removed from the waste water.
It is used in the primary filtration level of the wastewater treatment plant.

Water for life.

All of the above.

The chemicals present in paints, solvents, insecticides, motor oils, may kill microbes that help purify water.
Hence, it is recommended not to throw them down the drain.
The other options mentioned are biodegradable and hence won't kill the microorganism.

All of these.

Sand, fine gravel and medium gravel.

Suspended impurities in the water are called contaminants.

Motor oil and medicine hamper the degradation process.

He used an improperly sanitized public toilet.

All the above.

Biodegradation is occurring in the piles through the action of microorganisms that consume nutrients and transform the initial waste into a series of organic substances called compost.
Thus the material used in compost are biodegradable.

Kill the harmful microorganisms.

Eucalyptus trees.

The system of a network of pipes used for taking away wastewater from homes or public buildings to the treatment plant is known as sewerage.

Anaerobic bacteria.

None of the above

Drains get blocked by cooking oil and fats.

Drip irrigation.

The last step of primary treatment involves sedimentation, which causes the physical settling of matter.

Earthworm

All of the above

In a filtration plant, water is filtered using layers of sand, fine gravel and medium gravel.

Sanitation refers to public health conditions related to clean drinking water and adequate treatment and disposal of human wastes and sewage. Preventing human contact with feces is part of sanitation.
Sanitation at public places can be maintained by Proper drainage,Garbage management and Sufficient public toilet facilities.

Chlorination is used to treat wastewater in order to kill germs.

Biogas and sludge both are the products of wastewater treatment.

All of these.

Cooking oil should be thrown down in the wash basin.

Both Biogas and sludge

A very large fraction of our people defecates in the open, on dry riverbeds, on railway tracks, near fields and many a time directly in water.
Untreated human excreta is a health hazard. It may cause water pollution and soil pollution. Both the surface water and groundwater get polluted.
A septic tank is an underground chamber made of concrete, fiberglass or plastic through which domestic wastewater flows for basic treatment.
Settling and anaerobic processes reduce solids and organics, but the treatment efficiency is only moderate. Septic tank systems are a type of simple onsite sewage facility.
Chemical toilet is a toilet that is not connected to a sewage system but has a compartment in which waste is treated with chemicals for temporary storage.
Letting off drainage in rivers will cause water pollution.

Biodegradable

All of these.

Sewage network is, a network of pipes, pumps, and force mains for the collection of wastewater, or sewage, from a community.

Sewage is a liquid waste which causes water pollution as well as soil pollution.