No verified paper has been uploaded for GBPSC-PMS Environmental Science Set-8 yet.
The MCQs below are drawn from the Environmental Science subject category.
Showing 51–60
of 2378 MCQs
Page 6 / 238
51
Where is wastewater typically discharged after collection?
Wastewater, after undergoing various levels of treatment, is commonly discharged into surface water bodies such as rivers, lakes, or oceans. This practice is standard in municipal and industrial waste management systems, provided the effluent meets regulatory environmental standards to prevent ecosystem degradation.
52
In certain regions of Bangladesh, how far inland does saltwater intrusion extend?
Saltwater intrusion in Bangladesh is a significant environmental issue, particularly in the coastal districts. Studies indicate that saline water can penetrate up to 150 kilometers inland during the dry season, severely impacting freshwater availability, agriculture, and local ecosystems in the low-lying deltaic regions.
53
Which essential component is required to support the respiration and survival of aquatic organisms in water bodies?
Dissolved oxygen is critical for the survival of most aquatic organisms, including fish and invertebrates. These organisms rely on oxygen dissolved in the water column to perform cellular respiration. Levels of dissolved oxygen are a primary indicator of water quality and the overall health of an aquatic ecosystem.
54
How are wastewater treatment plants classified in terms of ecological systems?
An ecosystem is defined as a community of living organisms in conjunction with the nonliving components of their environment. Wastewater treatment plants are designed, constructed, and maintained by humans to perform specific ecological functions, such as nutrient removal and organic matter degradation, making them clear examples of artificial or man-made ecosystems.
55
What is the primary determinant of the chemical and physical composition of sewage water?
The composition of sewage, or wastewater, is fundamentally determined by its origin. Domestic sewage, industrial effluent, and agricultural runoff contain vastly different pollutants, chemicals, and biological loads. Therefore, identifying the source is the most critical step in characterizing the wastewater for appropriate treatment and management strategies.
56
Which type of solids remain suspended in sewage water?
Suspended solids are particles that are large enough to be held in suspension within the water column but are not dissolved. These particles can often be removed through physical processes like sedimentation or filtration in wastewater treatment plants.
57
Which gas is primarily responsible for the unpleasant odors often detected at waste treatment facilities?
Hydrogen sulfide (H2S) is a colorless gas produced by the anaerobic decomposition of organic matter in wastewater. It is well-known for its characteristic 'rotten egg' smell and is a common indicator of septic conditions in sewage treatment systems.
58
In the context of water quality analysis, what does the term 'fixed solids' represent?
In environmental chemistry, total solids are often divided into volatile and fixed components. Fixed solids are the residue remaining after a sample is ignited at a high temperature (typically 550 degrees Celsius). Since organic matter is burned off during this process, the remaining material consists primarily of inorganic minerals and salts, which are classified as fixed solids.
59
Wastewater contains a diverse community of microorganisms; besides bacteria, which of the following are commonly present?
Wastewater is a complex biological medium that supports various life forms. In addition to bacteria, which are the primary decomposers, fungi are frequently present, especially in environments with higher organic loads, as they play a role in breaking down complex organic compounds.
60
In a rural environmental context, what is the primary benefit of installing toilets?
The installation of toilets in rural areas is a fundamental intervention to improve hygiene factors. By providing a sanitary method for human waste disposal, it prevents the contamination of local water sources and reduces the transmission of fecal-oral diseases, thereby significantly improving public health outcomes and living standards in rural communities.
