Daily Quiz: UPSC Prelims Marathon – February 9, 2018

Photochemical smog is the chemical reaction of sunlight, nitrogen oxides and volatile organic compounds in the atmosphere, which leaves airborne particles and ground-level ozone. It may include the following:

• Aldehydes
• Nitrogen oxides, particularly nitric oxide and nitrogen dioxide
• Peroxyacyl nitrates
• Tropospheric ozone
• Volatile organic compounds

All of these harsh chemicals are usually highly reactive and oxidizing. Photochemical smog is therefore considered to be a problem of modern industrialization.  It is present in all modern cities, but it is more common in cities with sunny, warm, dry climates and a large number of motor vehicles like in Delhi.

Statement 1 is Incorrect:

The pyramid of numbers can either be upright for ex:  Pyramid seen in grassland ecosystem and pond ecosystem.

Or Inverted for ex: Tree ecosystem.

Statement 2 and 3 is correct:

• To compare the functional roles of the trophic levels in an ecosystem, an energy pyramid is most suitable.
• An energy pyramid represents the amount of energy at each trophic level and loss of energy at each transfer to another trophic level. Hence the pyramid is always upward, with a large energy base at the bottom.

• In many aquatic ecosystems, the pyramid of biomass may assume an inverted form. [Pyramid of numbers for aquatic ecosystem is upright]
• This is because the producers are tiny phytoplankton that grow and reproduce rapidly.
• Here, the pyramid of biomass has a small base, with the consumer biomass at any instant actually exceeding the producer biomass and the pyramid assumes inverted shape.

Western Himalaya refers to the western half of the Himalayan Mountain region, stretching from Badakhshan in northeastern Afghanistan/southern Tajikistan, through Kashmir to Nepal.

Eastern Himalaya is situated between Central Nepal in the west and Myanmar in the east, occupying southeast Tibet in China, Sikkim, North Bengal, Bhutan and North-East India.

Statement 1 is wrong :

The western himalayas consists of the most continuous range and the loftiest peaks and compared to eastern Himalayas.

The western Himalayas receive more precipitation from northwest in the winters, and eastern Himalayas receive more precipitation from southeastern monsoon in the summers.

Eastern Himalayas are much ahead from western Himalayas in terms of Biodiversity and is one of the Biodiversity hotspots

Plate Tectonic Theory:

Conservative Plate Boundaries

• Boundaries where the two plates slide past each other
• A plate is neither created nor destroyed in this case.
• A large amount of stress is released as the plates move against each other.
• Release of stress leads to shallow-focus intense earthquake.

Convergent Plate Boundaries

• Boundaries where the two plates move towards each other.
• Convergence leads to the sinking of the heavier tectonic plate under the lighter one.
• Benioff zone refers to a dipping planar zone of the earthquake that is produced by the interaction of a down-going oceanic crustal plate with a continental plate.
• At the point of subduction the rocks get broken due to compression.

Statement 1 is incorrect

Continental Crust

• Continental Crust is made up of Graniatic & Andesitic Rocks
• Dominant mineral present in this rock is Feldsphur
• Density of the Continental crust is 2.6 gm. / Cm3
• Thickness of the Continental crust is 40 km
• Under mountainous area thickness of Continental crust reaches up to 100km

Statement 2 and 3 are correct

Oceanic Crust

• Oceanic crust is made up of Basaltic Rocks
• Minerals composing the Oceanic crust is Ferro magnesia
• Density of the Oceanic crust is 3.0gm. / Cm3
• Thickness of the Oceanic crust is much less variable up to 5-10 km

1. Primary waves or P waves (longitudinal) (fastest)
2. Secondary waves or S waves (transverse) (least destructive)
3. Surface waves or L waves (transverse) (slowest) (most destructive)

Coastal landforms, any of the relief features present along any coast, the result of a combination of processes, sediments, and the geology of the coast itself.

There are two major types of coastal morphology: one is dominated by erosion and the other by deposition. They exhibit distinctly different landforms, though each type may contain some features of the other. In general, erosional coasts are those with little or no sediment, whereas depositional coasts are characterized by abundant sediment accumulation over the long term.

Erosional Landform-Sea cliff, Wave cut platform, sea stacks, sea arches

Depositional Landform: Deltas,Beaches,Coastal dunes,Barriers,spits