New species arise through a process called speciation. In speciation, an ancestral species splits into two or more descendant species that are genetically different from one another and can no longer interbreed.

In Phyletic speciation, a species changes gradually over a long period of time to become entirely different from the ancestor.

Sympatric speciation is the process through which new species evolve from a single ancestral species while inhabiting the same habitat.

Allopatric speciation – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model – is a mode of speciation that occurs when biological populations become geographically isolated from each other to an extent that prevents or interferes with gene flow.

The Citizenship Act, 1955, prescribes three ways of losing citizenship as below:

Renunciation, termination and deprivation.

If a citizen has, within five years after registration or naturalization, been imprisoned in any country for two years, his citizenship is compulsorily terminated by the Central Government,by Depreivation.

• Khanna is a city and a municipal council in the Ludhiana district of  Punjab. It is well known for being Asia's largest grain market.

• The mole ratio of hydrogen and oxygen gases liberated during the electrolysis of water is 2:1.

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• Revenue expenditure is for the normal running of Government departments and various services, interest payments on debt, subsidies, etc. Broadly the expenditure which does not result in creation of assets for Government of India is treated as revenue expenditure.
• This is expenditure incurred for purposes other than the creation of Physical or financial assets of the central government. It relates to those expenses incurred for the normal functioning of the government departments and various services, interest payments on debt incurred by the government and grants given to state governments and other parties. Apart from providing implicit subsidies through underpricing of public goods and services like education and health, the government also extends subsidies explicity on items such as exports, interest on loans, food and fertilizers.

Ans. C

Land-line telephone networks are full-duplex since they allow both callers to speak and be heard at the same time.

Full-duplex operation is achieved on a two-wire circuit through the use of a hybrid coil in a telephone hybrid. Modern cell phones are also full-duplex.

• Treaty of Amritsar, (April 25, 1809), pact concluded between Charles T. Metcalfe, representing the British East India Company, and Ranjit Singh, head of the Sikh kingdom of Punjab.

Radioactive isotopes can also be created for many elements. An isotope of uranium (Uranium-235) is used as a fuel in nuclear reactors. An isotope of cobalt (Cobalt-60) is used in the treatment of cancer.

An isotope of iodine (Iodine-131) is used in the treatment of goitre.

In Golaknath case (1967), the Supreme Court ruled that the Parliament cannot take away or abridge any of the Fundamental Rights, which are 'sacrosanct' in nature. In other words, the Court held that the Fundamental Rights cannot be amended for the implementation of the Directive Principles.

Sovereignty means the independent authority of the State, not being subject to the control of any other State or external power. The text declares India to be a “Republic” — indicating a government by the people and for the people. It states “social, economic, and political justice” as an objective.