Description

BZYCT 131 BSCG ignou assignment 2024

Course : BSCG
Session 2024
Submission date : This assignment is valid from 1st January, 2024 to 31st December, 2024.

1. a) Make a flow chart to show how animals can be classified according to
their level of organisation, symmetry, germ layers and developmental
patterns.
b) Define bilateral symmetry. What are the advantages that bilaterally
symmetrical animals have over radially symmetrical animals?
(5)
(5)
2. a) Describe the characteristic features of Cnidarians.
b) What do you mean by polymorphism? Expalin the functions of various
polymorphic forms of Hydrozoa.
(5)
(5)
3. What is parasitic adaptation? Explain the adaptations that have taken place in
Ascaris lumbricoides.

BZYCT 131 BSCG ignou assignment 2024

4. Write short notes on the following with suitable diagrams:
i) Book lungs of Arachnida
ii) Pectines of scorpions
(10)
5. a) What are the characteristics of echinderms that are unique to them and not
found in other phyla?
b) Describe the water vascular system of a seastar.
(5)
(5)
6. Give one word/short answer for the following:
i) Give one prominent difference between sharks and rays.
ii) What kind of tail characterises elasmobranchs?
iii) In what way are sharks well adapted for predatory life habit?
iv) What is the function of the lateral line system in elasmobranchs?
v) How is the Chimera different from sharks and rays?
(10)
7. i) Describe parental care in amphibians.
ii) Distinguish between anurans and urodeles.

BZYCT 131 BSCG ignou assignment 2024

8. What are the three main reptile lines that evolved from the amniotes during the
Mesozoic era and from which lineage did the present day reptiles evolve? How
would you distinguish among the anapsid, diapsid and synapsid types of skull.
(10)
9. The special adaptations of birds all contribute to two factors essential for flight
namely, more power and less weight. Explain how each of the following
contributes to one or the other or both:
(i) Endothermy
(ii) Respiratory system
(10)
(iii) Skeleton system
(iv) Excretory system.
10. a) List and give one function of the four glands of the skin.
b) Differentiate between horns and antlers and give an example each of an
animal with horn and an antler.