#Question id: 7259
#Unit 5. Developmental Biology
The mechanism that triggered to initiate limb bud formation involes:
A. making mesoderm instructive for limb formation
B. inducing epithelial-to-mesenchymal transitions
C. making mesoderm permissive for limb formation
D. inducing mesenchymal-to-epithelial transitions
E. specifying forelimb and hindlimb
Which of the following combinations are incorrect?
#Question id: 7260
#Unit 5. Developmental Biology
There are maternally-determined variations along the animal-vegetal axis that are necessary for normal development in sea urchin. Which of the following statements about regulation in sea urchin embryos is consistent with that fact?
#Question id: 7261
#Unit 5. Developmental Biology
The Turing model provides a framework for limb development. Following statements are regarding to this model:
A. In Turing’s model, morphogen A promotes the production of more morphogen A (autoactivation) as well as production of morphogen I. Morphogen I, however, inhibits the production of morphogen A (lateral inhibition).
B. In Turing’s model, morphogen A inhibits the production of more morphogen A (autoinhibition) as well as production of morphogen I. Morphogen I, however, promotes the production of morphogen A (lateral activation).
C. In Turing’s model, the reaction-diffusion dynamics can tell us how the limb bud acquires its proximal- distal polarity as well as how the number of digits is regulated at the distal tip of the limb.
D. The reaction-diffusion system has been proposed to be sufficient for establishing patterns of precartilage and noncartilage tissues.
E. According to this model, along the proximal-distal axis the AER dividing into two domains 1-the inhibitory domain 2-the active domain.
F. According to this model, along the proximal-distal axis the AER dividing into three domains 1-the inhibitory domain 2-the active domain 3-frozen domain.
Which of the following combinations are incorrect?
#Question id: 7262
#Unit 5. Developmental Biology
Match
the following Gene (column I) with their function (column II).
Column I |
Column II |
A.
sex-lethal |
i.
facilitates transcription from the X chromosome |
B.
double-sex |
ii.
help to generate the female phenotype
by splicing the doublesex gene |
C.
msl |
iii.
encodes an RNA splicing factor |
D.
transformer |
iv.
activate wingless gene in female |
Which
of the following is correct?
#Question id: 7263
#Unit 5. Developmental Biology
Following statements are regarding to the drosophila.
#Question id: 7264
#Unit 5. Developmental Biology
The Dictyostelia social
amoebas are found in a wide range of soil habitats. They can come together to
form a fruiting structure, in which a proportion of cells are sacrificed to
build the stalk and the remainder differentiate into resilient dormant spores.
This multicellular life cycle is common to all Dictyostelids. It consists
of an interconnected programme of cell movement and cell differentiation, and
has been intensively studied in the model organism D. discoideum. Few mutants
(Column A) and phenotypes (Column B) are listed in the table given below.
Column A |
Column B |
A.
Loss of function of cAMP-dependent
protein kinase (PKA) |
i.
cell develop normally but unable to germinate |
B.
Loss of function of RegA |
ii.
Loose aggregate form |
C.
Loss of function of adenylate cyclase B |
iii.
No aggregation |
D.
Loss of function of gp80 |
iv.
accumulation of cAMP and PKA activation |