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
211
A Life Cycle Assessment (LCA) evaluates impacts from:
Answer:
Cradle-to-grave stages
LCA quantifies inputs and outputs from raw material extraction to end-of-life. It identifies hot spots for improvement. “Cradle-to-cradle” considers closed-loop reuse.
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212
The best single index for measuring a population’s pressure on resources is the:
Answer:
est single index for measuring a population’s pressure on resources is the:
It estimates the biologically productive land and water needed to supply resources and absorb wastes. It allows comparison across countries and over time. Lower footprints imply lighter environmental pressure.
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213
The Montreal Protocol chiefly targets the phaseout of:
Answer:
hiefly targets the phaseout of:
CFCs destroy stratospheric ozone via catalytic chlorine cycles. The protocol’s controls have led to gradual ozone layer recovery. It is considered one of the most successful environmental treaties.
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214
The primary driver of the urban heat island effect is:
Answer:
Heat retention by concrete/asphalt
Dense built materials store heat during the day and release it at night, raising urban temperatures. Reduced vegetation lowers evaporative cooling. Waste heat from vehicles and buildings adds to the effect.
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215
A biodegradable plastic developed by Biopak (Australia) is:
Answer:
Biopol
“Biopol” is a trade name for polyhydroxyalkanoates (PHAs), biodegradable bioplastics produced by bacteria. PET and PVC are conventional, non-biodegradable polymers. Some polyesters can be biodegradable, but Biopol specifically refers to PHAs.
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Sweet—here are **50 fresh MCQs**, continuing the numbering from your last set. Same format: statement, options, **Correct Answer**, and a short **Explanation**.
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216
Permissible minimum thickness of plastic carry bags (common regulation) is:
Answer:
arry bags (common regulation) is:
Many jurisdictions mandate ≥50 microns to improve reusability and recyclability and reduce littering. Thicker bags are less prone to tearing and are more likely to be reused. Local rules can vary but 50 microns is widely accepted.
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217
Growing trees on a large scale is known as:
Answer:
large scale is known as:
Afforestation establishes forests on non-forested land. Reforestation restores forests where they were depleted. Agroforestry integrates trees with crops/livestock.
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218
The chief chemical element in the biosphere (by mass in organisms) is:
Answer:
Oxygen
In living matter, oxygen is abundant due to water content and biomolecules; carbon is also vital but less by mass. In Earth’s crust and oceans, oxygen dominates. Carbon is the backbone of organic compounds.
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219
Sulphur bacteria are examples of:
Answer:
acteria are examples of:
Sulfur-oxidizing bacteria are chemoautotrophs, using chemical energy (oxidizing reduced sulfur) to fix CO₂. They thrive in sulfide-rich environments. They don’t depend on organic food.
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220
The canopy is:
Answer:
Uppermost level of the forest
The canopy consists of the upper tree layer intercepting most sunlight. It shapes microclimates and habitats below. Understory and forest floor lie beneath.
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