Question Discussion & Solution

Here the pattern is,

The correct answer is 1-B, 2-A, 3-D, 4-C.

Key Points

Additional Information

The first two statements give information about payal, monika and Sonam. Information about kunal and monika cannot be determined.

Key Points 

• The biosphere reserves are the areas meant for the conservation of biodiversity.
• These are large areas of protected land for the conservation of wildlife, plant and animal resources and traditional life of the tribals living in the area.
• The biosphere reserves help to maintain the biodiversity and culture of that area.
• A biosphere reserve may also contain other protected areas.
• The Pachmarhi Biosphere Reserve consists of one national park named Satpura and two wildlife sanctuaries named Bori and Pachmarhi

Additional Information

• There are18 biosphere reserves in India:-
  • Cold Desert, Himachal Pradesh
  • Nanda Devi, Uttrakhand
  • Khangchendzonga, Sikkim
  • Dehang-Debang, Arunachal Pradesh
  • Manas, Assam
  • Dibru-Saikhowa, Assam
  • Nokrek, Meghalaya
  • Panna, Madhya Pradesh
  • Pachmarhi, Madhya Pradesh
  • Achanakmar-Amarkantak, Madhya Pradesh-Chhattisgarh
  • Kachchh, Gujarat
  • Similipal, Odisha
  • Sundarban, West Bengal
  • Seshachalam, Andhra Pradesh
  • Agasthyamala, Karnataka-Tamil Nadu-Kerala
  • Nilgiri, Tamil Nadu-Kerala 
  • Gulf of Mannar, Tamil Nadu
  • Great Nicobar, Andaman & Nicobar Island

The correct answer is Option(2).i.e.Alpha Decay.     

• In radioactivity, the emission consists of the Helium nucleus sustains under Alpha Decay. 
• Alpha Decay: 
  • It is basically responsible for the emission of the Helium nucleus. 
  • An alpha particle is consists of two neutrons & two protons which is the same as a helium nucleus.
  • We generally use 24He to implement an alpha particle which has a 2+ charge.
  • The original atomic number of the atom decreases by two (because of the loss of two protons), and its mass number decreases by four (because of the loss of four nuclear particles) when a radioactive atom throws down an alpha particle. 
• Emission of Alpha Particle: 
  •  The emission of an alpha particle can be present with a chemical equation: 
  • For example, the alpha-particle emission of uranium-235 is as follows:
       ²³⁵U₉₂→⁴He₂ + ²³⁵Th₉₀