General Science/Everyday Science MCQs
Topic Notes: General Science/Everyday Science
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
471
In environmental science, BOD stands for:
Answer:
Biological Oxygen Demand
BOD measures the amount of dissolved oxygen needed by microorganisms to break down organic matter in water. High BOD indicates pollution, as more oxygen is consumed during decomposition. It is an important parameter in assessing water quality.
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472
Which type of pollution is most likely to cause outbreaks of jaundice?
Answer:
Water pollution
Jaundice is often associated with hepatitis viruses spread through contaminated water. Polluted drinking water with pathogens is the leading cause of such outbreaks. Proper water sanitation and treatment are essential preventive measures.
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473
The loss of species in tropical countries is primarily due to:
Answer:
Deforestation
Deforestation leads to habitat loss, fragmentation, and reduced biodiversity in tropical ecosystems. While pollution and urbanization also contribute, large-scale forest clearing for agriculture and timber is the most significant cause. Tropical forests are biodiversity hotspots, making them highly vulnerable.
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474
The majority of Tiger Reserves in India are found in:
Answer:
Madhya Pradesh
Madhya Pradesh is known as the “Tiger State” of India because it has the highest number of tiger reserves. These reserves include Kanha, Bandhavgarh, Pench, and Satpura. Conservation efforts here play a major role in protecting India’s tiger population.
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475
Which chemical is commonly used to artificially ripen mangoes?
Answer:
Calcium carbide
Calcium carbide releases acetylene gas, which acts like ethylene to induce ripening. However, it is unsafe because it contains toxic impurities such as arsenic and phosphorus. Natural ripening agents like ethylene are preferred for health reasons.
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476
Climatic stress is primarily caused by imbalances in:
Answer:
All of the above
Climatic stress occurs when organisms face insufficient or excessive temperature, humidity, or radiation levels. These factors directly influence survival, reproduction, and ecosystem stability. Both extreme heat and inadequate sunlight can disrupt natural processes.
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477
When shopping, what action best supports environmental conservation?
Answer:
ction best supports environmental conservation?
Choosing products with minimal packaging reduces solid waste and energy consumption associated with packaging production. Small actions such as reusing bags and avoiding unnecessary packaging significantly reduce environmental impact. The other options encourage wasteful practices.
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478
Bacterial decomposition of organic matter under aerobic conditions is called:
Answer:
Composting
Composting is the natural, aerobic breakdown of organic material by microorganisms, producing nutrient-rich humus. Unlike fermentation, which is largely anaerobic, composting requires oxygen for effective decomposition. It is a sustainable way to recycle kitchen and agricultural waste.
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479
The least preferred method for disposing of municipal solid waste is:
Answer:
Incineration
Incineration is the least preferred method because it produces air pollutants, toxic ash, and requires significant energy. While it reduces waste volume, the environmental and health costs are high. Composting and briquetting recycle waste into useful products, and landfills remain common though not ideal.
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480
Which gas is most associated with global warming?
Answer:
ssociated with global warming?
CO₂ is the largest contributor to climate change. It comes mainly from burning fossil fuels. Methane is stronger per molecule but less abundant.
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