10 Questions • 5 Minutes • Current Affairs Mock Test in Hindi and English
• SO2 from volcanic eruptions reacts in the atmosphere to form aerosol particles.
• These aerosols reflect and scatter incoming sunlight, reducing the amount of solar radiation reaching Earth's surface — causing Global Cooling.
• Similarly, volcanic ash and dust also block sunlight, adding to the cooling effect.
• In contrast, volcanic CO2 is a greenhouse gas and contributes to Global Warming — this is the key difference to remember.
• Example: The Hunga Tonga volcanic eruption released massive amounts of methane into the stratosphere.
• Volcanic eruptions release both SO2 and CO2. While SO2 causes short-term cooling, CO2 is a greenhouse gas that drives long-term Global Warming.
• Human activities today emit far more CO2 than all volcanoes combined — an important fact for SSC exams.
• SO2 from volcanoes can also combine with water to form sulphuric acid, which causes Acid Rain — damaging soil, water, and crops.
• Volcanic ash and dust = short-term cooling; CO2 = long-term warming. This short vs long-term distinction is frequently tested.
• Brachycephalic Obstructive Airway Syndrome (BOAS) is a condition found in flat-faced (brachycephalic) dog breeds like pugs that suffer from severe breathing problems.
• The shape of the nostril is genetically determined — narrower nostrils restrict airflow, causing BOAS.
• A genetic link was found between nostril shape and breathing quality: this trait is heritable and can pass from parent dogs to puppies.
• The solution proposed is Selective Breeding — choosing parent dogs with healthier nostril shapes to reduce BOAS in future generations.
• India imports approximately 85–90% of its oil and gas, making it highly dependent on global energy markets.
• A large portion of this oil passes through the Strait of Hormuz — which lies between Oman + UAE on one side and Iran on the other.
• To reduce this dependency, India is planning the Middle East India Deep Water Pipeline (MEIDP) from Oman to Gujarat.
• High oil import bills directly weaken the Indian Rupee — as more dollars are needed to pay for imports, demand for USD rises and INR depreciates.
• A study of Greenland ice cores recorded 12,000 years of mercury deposits — showing that human impact on mercury pollution is much older than previously thought.
• Earlier models focused only on the last 500 years. New evidence shows the impact is at least 2,000 years old, dating back to the Bronze Age.
• Mining activities in Eurasia during the Bronze Age are identified as the main reason for early mercury level increases.
• Mercury pollution further accelerated during the 13th century and again during the Industrial Era due to large-scale mining and coal use.
• Earlier belief: Horse riding began around 2100 BCE. New study says it started as early as 3500 BCE — that is 1,000 years earlier.
• Evidence came from skeletal remains of the Yamnaya people (3200–2600 BCE) found in Eurasia, which showed bone changes typical of habitual horse riders.
• Horse riding enabled large-scale migration across Eurasian grasslands (steppes), the spread of languages, culture, and even altered the genetic map of Eurasia.
• Eurasia = combined landmass of Europe and Asia.
• Ferrocene is a classic organometallic compound discovered about 70 years ago. Its structure: one Iron (Fe) atom sandwiched between two Carbon rings.
• The new compound developed by IIT Madras/NISC replaces carbon rings with Boron rings, with Osmium (Os) at the centre instead of Iron — making it carbon-free.
• Boron is placed next to Carbon in the periodic table, so it can also form ring-like structures similar to carbon.
• This new compound opens possibilities for new catalysts, 2D boron-based materials, and advanced chemistry applications in the future.
• Both statements are correct.
• Statement 1 ✓ — Ultrasound waves are above the human hearing range (20 Hz–20 kHz). Humans cannot hear ultrasound regardless of its intensity.
• Statement 2 ✓ — Unlike X-rays, ultrasound does not ionize atoms and does not damage DNA, making it safer for medical use — including foetal imaging during pregnancy.
• Ultrasound therapy applications include: Medical imaging, Vision research, Glaucoma treatment, Brain stimulation, and Cancer therapy (HIFU — High Intensity Focused Ultrasound).
• 'Sonogenetics' = using ultrasound + genetic engineering to control specific neurons without surgery.
• Both statements are correct.
• CAD (Current Account Deficit) = when a country's total imports of goods, services exceed its total exports — the gap is the deficit.
• India's oil import is ~17% of total goods imports. Gold imports further add to the import bill. Both being paid in dollars directly widen the CAD.
• A high CAD: weakens the Rupee (more dollars demanded → INR depreciates), depletes foreign reserves, and creates economic stress.
• India's CAD was ~1.4% of GDP previously; it could rise to 2.5% of GDP — a significant concern.
• Statements 1 and 2 are correct. Statement 3 is INCORRECT.
• Statement 3 ✗ — As per the source, ultrasound-based ocular devices have NOT yet received US FDA clearance. Clinical use is still in research/testing phase.
• Sonogenetics works in two steps: (1) Genetic engineering adds a mechanosensitive protein gene into a neuron membrane; (2) Ultrasound activates those specific neurons when needed — without any surgical procedure.
• Applications being explored: restoring damaged vision (optic nerve damage), treating Glaucoma, brain stimulation, and cancer therapy using HIFU (High Intensity Focused Ultrasound).
• In 2025, around 16 glaucoma patients in China were treated using this approach.