Developmental Biology of Animals — DU B.Sc. (Prog.) Applied Life Sciences with Agrochemicals and Pest Management pertaining to Zoology Previous Year Question Papers

Agrochemicals and Pest Management Attempt four questions in all. Draw well-labelled diagrams wherever necessary. 1. (a) Define the following (any five) : 1×5=5 (iii) Fate map (iv) Cleidoic egg (v) Embryonic induction (vi) Cortical rotation (b) Distinguish between the following (any two) : 2×2=4 (i) Radial and Spiral cleavage (ii) Hemimatabolous and Holometabolous development (iii) Morphollaxis and Epimorphosis (c) Match the following : 1×4=4 Edwin G. Conklin ( ) Regeneration in Hydra Bisphenol A ( ) Discovery of germ layers Christian Pander ( ) Fate Map (d) Name the germ layer from which the following are derived : 0.5×4=2 (iii) Notochord (iv) GI tract lining 2. (a) Illustratively discuss various types of gastrulation movements. 5 (b) Enumerate various steps involved in chick gastrulation. Explain the migration of various cells through the primitive streak. Support your answer with well labelled drawings. 10 3. (a) Explain the process of external fertilization in sea urchin. 10 (b) Explain embryonic induction and enumerate the functions of primary organizer. 5 4. (a) Define metamorphosis. Compare and contrast the hormonal control of amphibian metamorphosis with insect metamorphosis. 8 (b) Explain the various types of placenta on histological basis in mammals, with well labelled diagrams. 7 5. (a) Explain various mechanisms of Regeneration seen in animals. Discuss the process of limb regeneration in salamanders in detail. 8 (b) Trace the sequence of events taken up during the process of in vitro fertilization. 7 6. Write notes on (any three) : 3×5=15 (a) Slow block to polyspermy (b) Egg membranes (d) Embryonic stem cells.