ZOO/VI/10 Student's Copy
2 0 1 8
6th Semester
ZOOLOGY
Paper ZL-X
Developmental Biology
Full Marks 55
Time 2½ hours
PART A—OBJECTIVE
Marks 20
The figures in the margin indicate full marks for the questions
SECTION—A
Marks 5
Tick the correct answer in the brackets provided 1×5=5
1. Parthenogenesis where individuals of either sexes may be produced is
arrhenotoky
thelytoky
amphitoky
cyclitoky
2. The type of placenta in human is
monodiscoidal placenta
bidiscoidal placenta
diffuse placenta
zonary placenta
/509 1 Contd.
3. Hormone responsible for the retention of juvenile characters is
bursicon
ecdysone
neotenin
thoracotrophic hormone
4. Formation of inside sheet by mass separation of layer of cells from an
epithelium is called
invagination
involution
ingression
delamination
5. Thalidomide is a teratogen which causes
Down's syndrome
anencephaly
cleft palate
phocomelia
SECTION—B
Marks 15
Write short notes on the following in not more than 5 to 8 sentences each
3×5=15
1. Spiral cleavage
2. Fate maps
3. Epiboly
4. Holometabolic development in insects
5. Transgenesis
ZOO/VI/10/509 2 Contd.
PART B—DESCRIPTIVE
Marks 35
The figures in the margin indicate full marks for the questions
1. What do you understand by in vivo and in vitro fertilizations? Explain the
process involved in in vivo fertilization.
OR
Describe the different types of eggs with suitable diagrams. 7
2. Describe the blastulation process in frog. 7
OR
What are extra-embryonic membranes? Explain the extra-embryonic
membranes in chick with their functions.
3. Explain the concept of organizer and induction giving suitable examples. 7
OR
What are morphogenetic fields? Explain the double-gradient theory.
4. Describe the process of metamorphosis and its hormonal regulation in
amphibian. 7
OR
Explain the mechanism of regeneration in vertebrates. 7
5. Write a note on the concept of ageing. 7
OR
What are stem cells? Explain the different types of stem cells giving
examples.