Science – Medium Level – GK Questions

B-cells (B-lymphocytes) differentiate into plasma cells that secrete antibodies specific to antigens. T-cells assist in cell-mediated immunity. Central to adaptive immune response. [[NCERT Biology Class 12]]

Calcination decomposes carbonate ores (e.g., ZnCO₃ → ZnO + CO₂) by heating in limited air. Roasting is for sulfide ores in excess air. Key step in metal extraction. [[NCERT Chemistry Class 12]]

Synapse is the junction where neurotransmitters transmit signals from one neuron to another. Essential for understanding nerve impulse transmission and brain function. [[NCERT Biology Class 11]]

Mangalyaan (Mars Orbiter Mission) made India the first Asian nation to reach Mars orbit (2014). It studied Martian surface and atmosphere. Important for current affairs and science sections. [[ISRO Reports, NCERT Geography Class 11]]

Natural selection is the mechanism of evolution where heritable traits enhancing survival/reproduction become more common over generations. Foundational concept in biology. [[NCERT Biology Class 12]]

Cellulose (in plant cell walls) is a natural polymer of glucose. Polythene, PVC, Nylon are synthetic polymers. Understanding polymer types is important for materials science. [[NCERT Chemistry Class 12]]

In stellar cores, hydrogen nuclei fuse into helium under extreme temperature/pressure, releasing vast energy (E=mc²). Fusion differs from fission (splitting heavy nuclei). Key astrophysics concept. [[NCERT Physics Class 12]]

Ozone (O₃) absorbs 97-99% of Sun's medium-frequency UV-B and UV-C rays, protecting life from DNA damage. Ozone depletion by CFCs is a major environmental concern. [[NCERT Chemistry Class 11, UNEP Reports]]

Phishing is social engineering (fraudulent emails) to steal credentials. Ransomware encrypts files for payment. Distinguishing cyber threats is important for digital literacy sections. [[CERT-In Guidelines, NCERT Computer Science]]

Generators work on electromagnetic induction (Faraday's Law): rotating coil in magnetic field induces current. Motors do the reverse. Crucial for power generation concepts. [[NCERT Physics Class 10]]

Nephrons filter blood, reabsorb nutrients, and produce urine. Each kidney has ~1 million nephrons. Understanding nephron structure is vital for physiology questions. [[NCERT Biology Class 11]]

Wavelength (λ) is the spatial period of a wave. Related to frequency (f) and speed (v) by v = fλ. Fundamental for understanding sound, light, and electromagnetic waves. [[NCERT Physics Class 11]]

Antibiotics target bacterial cell structures/processes. Viruses lack these targets and require antivirals or vaccines. Misuse of antibiotics causes resistance—a major public health issue. [[NCERT Biology Class 12, WHO Guidelines]]

Like poles (N-N or S-S) repel; unlike poles (N-S) attract. This fundamental law of magnetism applies to bar magnets, electromagnets, and Earth's magnetic field. [[NCERT Physics Class 10]]

Atomic number (Z) = proton count, defining an element's identity and position in periodic table. Mass number = protons + neutrons. Foundational concept in chemistry. [[NCERT Chemistry Class 11]]

India hosts ~7-8% of global species despite having 2.4% of land area. It has four biodiversity hotspots: Himalayas, Indo-Burma, Sundaland, Western Ghats. Important for environment and geography sections. [[MoEFCC Reports, NCERT Biology Class 12]]

1 kWh = energy consumed by a 1 kW device running for 1 hour = 3.6×10⁶ Joules. Electricity bills use kWh. Understanding units is crucial for numerical problems. [[NCERT Physics Class 10]]

Standard gravity (g) is 9.8 m/s², varying slightly with altitude and latitude. It's derived from Newton's law of gravitation (g = GM/R²). Essential for mechanics problems in physics. [[NCERT Physics Class 11]]

Decomposers break down dead organisms, recycling nutrients (nitrogen, phosphorus) into soil for producers. This sustains ecosystem productivity and is vital for biogeochemical cycles. [[NCERT Biology Class 12]]

The 2015 Paris Agreement targets limiting global temperature rise to well below 2°C, preferably 1.5°C, to mitigate climate change impacts. India is a signatory committed to Nationally Determined Contributions (NDCs). [[UNFCCC, NCERT Geography Class 11]]