What is divergent evolution? Explain taking an example of plants.

2

(a)

Why are the wings of butterfly and birds said to be analogous organs? Name the type of evolution, the analogous organs are a result of.

2

(a)

When we say 'survival of the fittest', does it mean that:
(a) those whose are fit only survive or 
(b) those that survive are called fit? Comment.

2

(a)

Explain the origin of universe.

2

(a)

Write the names of two dinosaurs that lived early in the history of earth and two others that lived little later.

2

(a)

Who proposed the biogenetic law? Who disapproved it? Why?

2

(a)

A chimpanzee can hold objects by its hands and an elephant by its trunk. Are these organs analogous or homologous? Give reasons in support of your answer.

2

(a)

Name the largest of the dinosaurs and mention two of its features.

2

(a)

How can you explain the existence of analogous organs?

2

(a)

When was the earth formed? What were its conditions at that time?

2

(a)

Rearrange the following in increasing order ofM evolution:Gnetales;Ferns;Zosterophyllum;Ginkgo.

2

(a)

Write the Oparin and Haldane's hypothesis about the origin of life on earth. How does meteorite analysisfavour this hypothesis?

2

(a)

Write the formula to calculate allele frequency in future generations according to Hardy- Weinberg equilibrium

2

(a)

Penicillin was once called wonder drug as it could heal most of the bacterial infections. It is no longer used now. Suggest the possible reasons for this.

2

(a)