Questions for 16 July zoology

Q:-1 Describe the general feature and life cycle of Nereis and compare its general body plan with earthworm. (20)

Q:-2 Define linkage. How concept of linkage had  established? Discuss its significance with examples. (15)

Q:-3 Female Drosophila with cinnabar eye (cn) and vestigial wings (vg) were mated to males with roof wings (rf). The F1 were all wild-type. When the F1 females were test crossed with males homozygous for all three traits the following result were obtained.
382 cinnabar, vestigial P
401 roof       P
3 cinnabar DCO  
4 roof, vestigial DCO
59 cinnabar, roof, vestigial SCO1
67 wild SCO1
44 cinnabar, roof SCO2
40 vestigial SCO2
Calculate following
a) gene order
b) Interference
Draw gene map.  (20)

Q:-4 What is recombination? Discuss its significance. (10)

Q:-5 Describe the life cycle of Leach with well labelled diagrams. (15)

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