#Question id: 7190
#Unit 5. Developmental Biology
In
amphibia, few mutants (Column A) and their affected event or organ (Column B).
|
Column A |
Column B |
|
I.
mRNA of cadherin is destroyed by antisense oligonucleotides |
a.
Epiboly |
|
II.
Loss of methylation on H3K4 |
b.
Convergent extension |
|
III.
Loss of function of tbxt gene |
c.
Blastocoel |
|
IV.
Knockdown of C3a with antisense morpholinos |
d.
MBT |
|
V.
Inhibition of PCP pathway |
e.
Notochord |
Which of the following is correct?
#Question id: 7191
#Unit 5. Developmental Biology
In tunicate embryo, Presumptive endoderm originates from the vegetal A4.1 and B4.1 blastomeres. The specification of these cells coincides with the localization of β-catenin. Which of the following statement is incorrect?
#Question id: 7192
#Unit 5. Developmental Biology
The following are statements regarding the development and maintenance of anterior and posterior compartments in each segment of Drosophila. Which of the following is correct?
#Question id: 7193
#Unit 5. Developmental Biology
Some statements with respect to the regeneration in hydra.
A. The major head inducer of the hypostome organizer is a set of Wnt proteins acting through the canonical B-catenin pathway.
B. The major head inducer of the hypostome organizer is a set of Wnt proteins acting through the noncanonical B-catenin pathway.
C. These Wnt proteins are seen in the apical end of the early bud, defining the hypostome region as the bud elongates
D. If the Wnt signaling inhibitor GSK3 is itself inhibited throughout the body axis, ectopic tentacles form at all levels, and each piece of the trunk has the ability to stimulate the outgrowth of new buds.
E. transgenic hydra made to globally misexpress the downstream Wnt effector ectopic tentacles form at all levels, and each piece of the trunk has the ability to stimulate the outgrowth of new buds.
Which of the following statements are incorrect?
#Question id: 7194
#Unit 5. Developmental Biology
Formation
of digits and sculpting the tetrapod limb requires death of specific cells in
the limb in a programmed manner. Which one of the following interactions could
explain proper limb formation?
#Question id: 7195
#Unit 5. Developmental Biology
Given below are some of the statements regarding toll signalling pathway in drosophila.
A. Dorsal protein is a transcription factor with homology to the Rel/nuclear factor kappa B (NFκB) family of vertebrate transcription factors, which are involved in regulation of gene expression in vertebrate immune responses.
B. Toll signalling pathway is also used in the adult fly in defense against infection.
C. In the Drosophila embryonic Toll pathway Dorsal is held inactive in the nucleus by the protein Cactus.
D. The ligand for Toll is a fragment of the protein Easter, which is generated in the ventral vitelline space by the protease Spatzle.
E. When Toll is activated by binding the Spätzle fragment, its cytoplasmic domain binds a complex of the adaptor proteins dMyD88 and Tube. Tube interacts with, and activates, the protein kinase Pelle.
F. Activation of Pelle leads to the dephosphorylation of Cactus. This releases Dorsal, which is then free to enter a nucleus.
Choose the most appropriate combination of correct statements: