The concept of chemical evolution is based on 

1. crystallization of chemicals

2. interaction of water, air, and clay under intense heat

3. effect of solar radiation on chemicals

4. the possible origin of life by the combination of chemicals under suitable environmental conditions

Which one of the following describes correctly the homologous structures?

Correct order is [1991]
1. Palaeozoic $\stackrel{<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>}{\to }$ Archaeozoic $\stackrel{<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>}{\to }$Coenozoic
2. Archaeozoic $\stackrel{<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>}{\to }$ Palaeozoic $\stackrel{<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>}{\to }$ Proterozoic
3. Palaeozoic $\stackrel{<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>}{\to }$Mesozoic $\stackrel{<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>}{\to }$ Coenozoic
4. Mesozoic $\stackrel{<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>}{\to }$Archaeozoic $\stackrel{<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>}{\to }$ Proterozoic

Which was absent in the atmosphere at the time of origin of life?

1. NH₃

2. H₂   

3. O₂   

4. CH₄

Evolutionary convergence is the development of 

1. common set of characters in the group of different ancestry

2. dissimilar characters in closely related groups

3. common set of characters in closely related groups

4. random mating

The finches of Galapagos islands provide an evidence in favour of

1. special creation

2. evolution due to mutation

3. retrogressive evolution 

4. biogeographical evolution 

What is genetic equilibrium?

The presence of the monotremes and marsupials in the Australian continent can be explained by:

1.  Convergent evolution

2.  Adaptive radiation

3.  Punctuated equilibrium

4.  Gene flow 

Which of the following would lead to deviation from Hardy-Weinberg equilibrium?

1. Random mating

2. Lack of mutations

3. No gene flow or gene migration

4. Natural selection

The now extinct reptile group that evolved into mammals was:

1. Therapsids

2. Dinosaurs

3. Thecodants

4. Sauropsids