No. of Printed Pages: 12 ILSE-06 1
BACHELOR OF SCIENCE (B.Sc.)
Term-End Examination
December, 2016

02464
LIFE SCIENCE LSE-06 DEVELOPMENTAL BIOLOGY
Time: 2 hours Maximum Marks: 50
Note: Answer Part I and Part II in separate answer copies. Answer the questions as per instructions given in each part. Draw well-labelled diagrams, wherever necessary.
PART I
(Plant Development)

Note: Question no. 1 is compulsory. Attempt any four questions from questions no. 2 to 7.

1. Fill in the blanks 6x1/2=3

of tapetum is characterized by the movement of protoplasts into anther locule.

Development of embryo from an unfertilized egg cell is called

is a piece of plant tissue that is used to start a culture.

The hormone delays senescence.

A large vacuole is present at the micropylar end of cell of
embryo sac.

The study of annual (growth) rings in tree trunks to learn about past climatic conditions is known as

Write the appropriate technical term for the following: 4x 1/2

Innermost layer of integument that is specialized to supply nutrients to embryo sac in ovules lacking nucellus.

The yellow-orange substance found outside mature pollen grains of many insect pollinated species.

Mechanism of self-dispersal of seeds.

The process of formation of sporophyte from the gametophyte without sexual process.

2. Write short notes on any two of the following: 2 x 2

Suspensor

Endosperm haustoria

Vascular cambium

Somatic hybridisation.


3. Write down two important differences between any two of the following: 2 x 2

Zygotic and Nucellar polyembryony

Heartwood and Sapwood

Gametophytic and Sporophytic self-incompatibility

Monosporic and Tetrasporic type of embryo sac development

4. Why is· cross pollination considered more advantageous as compared to self-pollination Describe any two mechanisms/devices adapted by flowering plants to prevent self-pollination. 5

5. Write a brief account on the synergistic and sequential effects of hormones. 3

Write an explanatory note on phytochrome.

6. What are androgenic haploids Discuss their importance in agriculture. 5

7. Describe the structure and functions of synergids. 3

Write a note on periderm. 2


PART II

(Animal Development)

Note: Question no, 8 is compulsory. Attempt any four questions from questions no. 9 to 14.

8. Distinguish between the following: 3x1=3

Isogamy and Anisogamy

Epiboly and Emboly

Allometric and Isometric growths

Fill in the blanks with appropriate words: 2x1=2

Vitellogenesis occurs during the stage of the prophase of Meiosis I.

An enzyme is released from the acrosome of the sperm head which removes the external cellular matrix and disperses the corona radiata.

9. Describe the prevention of polyspermy by slow block. 5

10. Summarize in a table various morphological and biochemical metamorphic changes in anurans. 5

11. What do you understand by spiral cleavage? 3

Describe in brief the process of metastasis. 2

12. Define Fate maps and describe how they can be constructed. 5

13. Describe neurulation in chick embryo. 5

14. Give various steps in limb regeneration in Salamander. 5