I: | is the subfield of biology that studies the evolutionary processes (natural selection, common descent, speciation) that produced the diversity of life on Earth. |
II: | is also defined as the study of the history of life forms on Earth. |
Assertion (A): | When we look at stars on a clear night sky we are, in a way, looking back in time. |
Reason (R): | When we see objects in our immediate surroundings we see them instantly and hence in the present time. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |
1. | 20 billion years back | 2. | 10 billion years back |
3. | 4.5 billion years back | 4. | 3.0 billion years back |
I: | Water vapour, methane, carbon dioxide, and ammonia released from molten mass covered the surface. |
II: | The UV rays from the sun broke up water into Hydrogen and Oxygen and the lighter H2 escaped. |
III: | Oxygen combined with ammonia and methane to form water, CO2, and other gases. |
IV: | As it cooled, the water vapour fell as rain, filling all the depressions and forming oceans. |
Which theory, regarding the origin of life, is alternatively also called “panspermia”?
1. | Special Creation | 2. | Spontaneous Generation |
3. | Cosmozoan Theory | 4. | Biochemical Evolution |
The theory of spontaneous generation stated that:
1. | life arose from living forms only |
2. | life can arise from both living and non-living |
3. | life can arise from non-living things only |
4. | life arises spontaneously, neither from the living nor from the non-living |
I: | The first form of life could have come from pre-existing non-living organic molecules (e.g. RNA, protein, etc.) |
II: | The formation of life was preceded by chemical evolution, i.e., the formation of diverse organic molecules from inorganic constituents. |
For the stability of the organic compounds, Oparin opined that, probably:
1. | UV radiation never reached the surface of the primeval Earth |
2. | the primeval Earth was in a molten state |
3. | the primeval Earth atmosphere was reducing rather than oxidizing |
4. | plenty of energy sources were available for chemical reactions to occur |
In 1953, S. L. Miller created primitive earth conditions in the laboratory and gave experimental evidence for the origin of the first form of life from pre-existing non-living organic molecules. The primitive earth conditions created include:
1. | low temperature, volcanic storms, an atmosphere rich in oxygen |
2. | low temperature, volcanic storms, reducing atmosphere |
3. | high temperature, volcanic storms, non-reducing atmosphere |
4. | high temperature, volcanic storms, reducing atmosphere containing CH4, NH3 etc. |