Health, Environment and Agriculture: RAS Prelims MCQs
662 RAS Prelims practice MCQs on health, environment and agriculture are on this page, in 4 chapters. They cover human health, food, nutrition and public health programmes, environmental and ecological changes and impact assessment, biodiversity and conservation of natural resources, and agriculture, horticulture, forestry and animal husbandry in Rajasthan. Each question has an answer and an explanation.
Practice questions based on the RPSC RAS Prelims syllabus. They follow the exam pattern but are not past-paper questions.
Showing 181–190 of 662 questions
Browse Health, Environment and Agriculture chapters
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q181. Given below are two statements, one is labelled as Assertion (A) and the other as Reason (R): Assertion (A): Excessive discharge of nutrients into lakes leads to a decrease in dissolved oxygen. Reason (R): Nutrient enrichment promotes rapid algal blooms, which consume oxygen upon death and decomposition.
Explanation
When water bodies receive an excess of nutrients, it triggers a rapid increase in the population of microscopic aquatic plants. While these organisms produce oxygen during the day, their eventual death leads to a massive decomposition process by bacteria. This biological breakdown consumes vast amounts of the oxygen dissolved in the water, creating a hostile environment for fish and other aquatic life.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q182. Eutrophication of water bodies is predominantly caused by an excess of:
Explanation
The process of nutrient enrichment in lakes and slow-moving rivers is primarily driven by two specific elements. These substances are commonly found in fertilizers used in agriculture and in domestic sewage. When they wash into water bodies, they act as powerful fertilizers for algae. The resulting overgrowth disrupts the natural balance of the ecosystem, leading to decreased water clarity and oxygen depletion.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q183. Biochemical Oxygen Demand (BOD) is a measure of:
Explanation
Scientists use a specific test to determine the level of organic pollution in a water sample. This measure quantifies the amount of dissolved oxygen required by microorganisms to break down the organic material present over a set period. A high value indicates that the water is heavily contaminated with waste, as more oxygen is needed for the bacteria to complete the decomposition.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q184. Minamata disease is a neurological syndrome caused by severe poisoning of:
Explanation
A severe neurological condition first discovered in a coastal Japanese town was linked to the industrial discharge of a toxic heavy metal into the local bay. The chemical transformed into an organic form that accumulated in fish and shellfish. People who consumed the contaminated seafood suffered from symptoms like loss of coordination and muscle weakness, illustrating the dangers of mercury in the environment.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q185. What is the primary purpose of the ‘Activated Sludge Process’ in wastewater treatment?
Explanation
During the treatment of wastewater, a biological stage is used to break down dissolved and suspended organic matter. This process involves mixing the water with a concentrated population of bacteria and other microorganisms in an aerated tank.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q186. High concentrations of fluoride in drinking water cause which of the following conditions?
Explanation
While small amounts of a certain mineral can help prevent tooth decay, excessive intake through drinking water over a long period causes serious health problems. The most severe form of this condition affects the bones, leading to pain and permanent deformities. This issue is particularly prevalent in regions where the groundwater naturally contains high concentrations of the mineral due to local geological formations.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q187. Which of the following correctly pairs a water pollutant with its associated health effect?
Explanation
Different chemical contaminants in water are linked to specific medical conditions. For example, high levels of a particular nitrogen compound are known to interfere with the blood’s ability to carry oxygen, especially in infants. This condition, often caused by runoff from fertilized fields, results in a characteristic bluish tint to the skin and can be life-threatening if the exposure is not stopped.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q188. Match List I with List II regarding wastewater treatment:
Wastewater Treatment Stage
Associated Process
A. Primary Treatment
i. Biological degradation of organic matter
B. Secondary Treatment
ii. Chlorination or UV radiation
C. Tertiary Treatment
iii. Physical settling and screening
D. Disinfection
iv. Advanced nutrient and chemical removal
Explanation
Cleaning wastewater involves several distinct steps. The initial phase uses physical methods like screening and settling to remove large solids. The next stage employs biological processes where microorganisms digest dissolved organic matter. More advanced techniques are then used to target specific nutrients and chemicals. Finally, the water is treated with chemicals or radiation to kill any remaining harmful bacteria before it is reused.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q189. The ‘Ganga Action Plan’ in India was launched primarily to:
Explanation
A major national initiative was launched to address the severe pollution in one of the world’s most significant rivers. The primary objective was to improve the quality of the water by reducing the amount of untreated domestic and industrial waste being discharged. This was achieved through the construction of numerous sewage treatment plants and the diversion of sewage away from the main river.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q190. The presence of coliform bacteria in a water sample indicates:
Explanation
Testing for a specific group of microorganisms that are naturally found in the intestines of warm-blooded animals is a standard way to assess water safety. Their presence in a sample serves as a clear warning that the water has been contaminated with waste from humans or animals. This indicator suggests that dangerous pathogens could also be present, making the water unsafe for drinking.
Answer key for these questions
Q
Correct answer
181
(a) Both A and R are true and R is the correct explanation of A.
182
(d) Nitrogen and Phosphorus
183
(c) Oxygen needed by bacteria for decomposition
184
(b) Methylmercury
185
(d) Secondary treatment to reduce organic matter
186
(a) Skeletal fluorosis
187
(c) Nitrate - Methemoglobinemia
188
(a) A-iii, B-i, C-iv, D-ii
189
(d) Improve water quality via sewage treatment
190
(b) Fecal contamination
Key facts from Health, Environment and Agriculture
The RPSC General Science syllabus includes human health and nutrition, environmental change, biodiversity and the agriculture of Rajasthan.
Health questions pair a deficiency or a programme with its cause or target, for example iron with anaemia.
Environment questions cover ecosystems, pollutants, laws and treaties, including carbon markets.
Rajasthan agriculture questions deal with dryland farming, crops of the arid zones and the State’s agro-climatic zones.
Science and technology, policies and defence are on the Science and Technology page.
Frequently asked questions
How many RAS Prelims practice MCQs are there on Health, Environment and Agriculture?
This page has 662 practice MCQs on Health, Environment and Agriculture. Each has the correct answer, and most have an explanation.
Which chapters does this set cover?
Four chapters: human health, food, nutrition and public health programmes; environmental and ecological changes and their impact assessment; biodiversity, conservation of natural resources and sustainable development; and agriculture, horticulture, forestry and animal husbandry in Rajasthan.
Are health, environment and agriculture part of the RAS Prelims syllabus?
Yes. The General Knowledge and General Science paper includes human health, nutrition, environment, biodiversity and the agriculture sector of Rajasthan, so these topics can be asked every year.
How can I revise this part of the syllabus?
Make short lists of deficiency diseases, pollutants, laws and treaties, and Rajasthan crops and zones. Attempt each chapter, read the explanations of the misses and revisit the lists after a few days.
