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 221–230 of 662 questions
Browse Health, Environment and Agriculture chapters
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q221. Consider the following greenhouse gases and their contribution to the natural greenhouse effect: A. Methane B. Water vapor C. Carbon dioxide Which of the following represents the correct sequence in decreasing order of overall contribution?
Explanation
Several different substances contribute to the natural warming of the planet. The most significant contributor by far is the gas that forms clouds and humidity. This is followed by a gas released through both natural and human activities like burning fuels. Other potent gases exist in much smaller concentrations but still play a role in the complex interactions that maintain the Earth’s temperature.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q222. Global warming is best defined as:
Explanation
The long-term increase in the Earth’s average surface temperature is driven primarily by human activities that release heat-trapping gases. Unlike seasonal weather changes or localized heating in cities, this phenomenon affects the entire planet over decades and centuries. It results in widespread changes to weather patterns, rising sea levels, and significant disruptions to ecosystems and human societies across all continents and oceans.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q223. Albedo effect is crucial in global warming discussions. What happens when Arctic sea ice melts?
Explanation
The reflectivity of the Earth’s surface plays a critical role in the global climate. Bright surfaces like ice reflect most of the incoming sunlight back into space. When this ice melts and is replaced by dark ocean water, the amount of energy absorbed by the planet increases. This feedback loop accelerates the warming process, leading to even more ice loss and higher temperatures.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q224. Identify the incorrect statement concerning greenhouse gases.
Explanation
While human activities are major sources of various greenhouse gases, many also occur naturally. For example, a potent heat-trapping gas is produced not only by industrial processes but also through biological decomposition in wetlands and the digestive systems of certain animals. Understanding both the natural and anthropogenic sources of these gases is essential for developing effective strategies to manage their atmospheric concentrations.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q225. The melting of permafrost in the Arctic is a major concern because it threatens to release massive amounts of which potent greenhouse gas?
Explanation
In the cold regions of the north, the ground remains frozen throughout the year, trapping large amounts of ancient organic matter. As temperatures rise and this frozen layer thaws, microbes begin to break down the material. This biological process releases a powerful greenhouse gas into the atmosphere. This release is a major concern because it can trigger further warming and even more rapid melting.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q226. How do higher global temperatures directly affect sea levels?
Explanation
Rising global temperatures cause sea levels to increase through two primary physical processes. First, the heat causes glaciers and polar ice sheets to melt, adding more liquid water to the oceans. Second, as the ocean water itself warms up, it physically expands and takes up more space. Together, these factors lead to a steady rise in the average height of the world’s seas.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q227. Given below are two statements, one is labelled as Assertion (A) and the other as Reason (R): Assertion (A): Carbon dioxide is the most significant anthropogenic greenhouse gas despite having a lower global warming potential than methane. Reason (R): Carbon dioxide is present in the atmosphere in much larger concentrations and persists for a longer duration than methane.
Explanation
While some gases are more potent at trapping heat than others, their total impact depends on their concentration and how long they remain in the air. Carbon dioxide is released in massive quantities from burning fossil fuels and stays in the atmosphere for centuries. Therefore, even though a molecule of methane is more effective at absorbing radiation, the sheer volume of carbon dioxide makes it the primary driver.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q228. The ozone layer is predominantly found in which layer of the Earth’s atmosphere?
Explanation
The Earth’s atmosphere is divided into several distinct layers based on temperature and composition. A specific region containing a high concentration of a three-atom oxygen molecule is located above the lowest layer where weather occurs. This protective shield sits between approximately fifteen and thirty-five kilometers above the surface. Its presence is vital for life because it filters out most of the sun’s harmful ultraviolet radiation.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q229. What is the primary function of the stratospheric ozone layer?
Explanation
High in the atmosphere, a thin layer of gas performs a critical role in protecting all living things on Earth. It acts as a natural filter, absorbing the majority of the high-energy ultraviolet radiation from the sun. Without this shield, this radiation would reach the surface in amounts that could cause widespread damage to DNA, increase skin cancer rates, and harm many different types of ecosystems.
RAS PrelimsHealth, Environment and Agriculture · Environmental and Ecological Changes and Impact Assessment
Q230. Chlorofluorocarbons (CFCs) cause ozone depletion primarily because:
Explanation
Certain synthetic chemicals were once commonly used in cooling systems and aerosol cans. When these stable compounds reach the upper atmosphere, they are broken down by intense sunlight. This reaction releases a highly reactive element that can destroy thousands of ozone molecules through a series of chemical cycles. This process leads to a significant thinning of the protective layer that filters ultraviolet radiation.
Answer key for these questions
Q
Correct answer
221
(a) B, C, A
222
(d) Long-term heating of climate system
223
(a) Albedo decreases, increasing absorption
224
(b) Methane is exclusively produced by industrial activities.
225
(b) Methane
226
(a) Via thermal expansion and ice melting
227
(a) Both A and R are true and R is the correct explanation of A.
228
(c) Stratosphere
229
(b) It absorbs harmful solar UV radiation
230
(d) They release ozone-destroying chlorine
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.
