Biogeography - GK Questions and Answers for competitive exams on Geography | page-13

Answer: Option [D]

The correct answer is Millions of years. The first known single-celled organisms appeared on Earth about 3.5 billion years ago, roughly a billion years after Earth formed. More complex forms of life took longer to evolve, with the first multicellular animals not appearing until about 600 million years ago.

Answer: Option [C]

The horizontal layers of soils are known as soil horizons. A soil profile is a vertical cross-section of the soil, made of layers running parallel to the surface. These layers are known as soil horizons. The soil is arranged in layers or horizons during its formation. These layers or horizons are known as the soil profile.

Answer: Option [B]

Central zoo authority of India was constituted in 1972. The Central Zoo Authority has been constituted under the section 38A of Wild Life (Protection) Act 1972. The Authority consists of a Chairman, ten members and a Member Secretary. The main objective of the authority is to complement the national effort in conservation of wild life.

Answer: Option [C]

The height of Australian Eucalyptus can reach over 70 metres. Mature mountain ash (E. regnans) trees are usually between 55 and 75 metres high, in tall forest.

Answer: Option [B]

The correct answer is Tidal energy. Tidal currents are highly predictable. Low and high tides follow well-known cycles, making it easier to know when power will be produced throughout the day. It also makes it easy to know how much power will be produced by turbines, since the power of the tides and currents can be forecasted accurately.