Daily Quiz #63 UPSC Prelims Marathon – January 16, 2020

Explanation: Methane is created and released into the atmosphere by biological processes that occur in an anaerobic environment. Methane absorbs terrestrial infrared radiation that would otherwise escape to space once methane is released into the atmosphere. This characteristic can lead to the warming of the atmosphere; hence methane is a greenhouse gas.
Methane emission levels from a source can vary significantly from one country or region to another, depending on many factors such as climate, industrial and agricultural production characteristics, energy types and usage, and waste management practices.
For example, moisture and temperature can affect the anaerobic digestion process, which is one of the key biological processes that cause methane emissions in both human-related and natural sources. Also, the implementation of technologies to capture and utilize methane from sources such as landfills, coal mines, and manure management systems affects the emission levels from these sources.
The largest source of methane emissions come from the decomposition of wastes in landfills, ruminant digestion and manure management associated with domestic livestock, natural gas and oil systems, and coal mining.

Explanation: INS Chakra II is a Russian Akula-class nuclear-powered attack submarine. It is operated by Indian Navy on a lease for 10 years. It was formally commissioned into service in India in April 2012 and is expected to be returned to Russia in 2022.
Arihant-Class: India is expected to build between three to six nuclear powered ballistic missile submarines (SSBNs) under its ATV Program. The first vessel in this class, INS Arihant, was commissioned in 2014. It is powered by an 83MW pressurized light-water reactor (PWR) fueled with enriched uranium. The Arihant-class submarines are 110 meters long with an 11-meter-wide beam and can travel up to 24 knots when submerged. They can remain submerged for about 50 days without surfacing. Their weapons systems are capable of firing torpedoes and submarine-launched ballistic missiles. However, the next ships in the class, after INS Arihant are expected to be larger and more powerful in terms of both firepower and nuclear power.

Explanation: There is only one planet we know of so far that is teeming with life––Earth. And on our planet, water is a critical ingredient for life as we know it. While astronomers still don’t know whether there’s life on other planets, they narrow the search for potentially habitable worlds using a handful of criteria. Because our blueprint for life is Earth, astronomers look for planets with Earth-like characteristics, like liquid water. But a celestial object can only orbit so close (like Mercury) or so far (like Pluto) from its star before water on its surface boils away or freezes. The ‘Goldilocks Zone,’ or habitable zone, is the range of distance with the right temperatures for water to remain liquid. Discoveries in the Goldilocks Zone, like Earth-size planet Kepler-186f, are what scientists hope will lead us to water––and one day life.

Explanation: Hepatitis refers to an inflammatory condition of the liver. It’s commonly caused by a viral infection, but there are other possible causes of hepatitis. These include autoimmune hepatitis and hepatitis that occurs as a secondary result of medications, drugs, toxins, and alcohol. Autoimmune hepatitis is a disease that occurs when your body makes antibodies against your liver tissue.
Pneumonia is an infection of the lungs with a range of possible causes. It can be a serious and life-threatening disease. It normally starts with a bacterial, viral, or fungal infection. The lungs become inflamed, and the tiny air sacs, or alveoli, inside the lungs fill up with fluid. Pneumonia can occur in young and healthy people, but it is most dangerous for older adults, infants, people with other diseases, and those with impaired immune systems.
Tetanus, also called lockjaw, is a serious infection caused by Clostridium tetani. This bacterium produces a toxin that affects the brain and nervous system, leading to stiffness in the muscles. If Clostridium tetani spores are deposited in a wound, the neurotoxin interferes with nerves that control muscle movement. The infection can cause severe muscle spasms, serious breathing difficulties, and can ultimately be fatal. Although tetanus treatment exists, it is not uniformly effective. The best way to protect against tetanus is to take the vaccine.

Explanation: The seven NASA spacecraft to reach Mars are Viking 1, Viking 2, Pathfinder, Spirit, Opportunity, Phoenix and Curiosity.