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#Question id: 12835

Following statements are regarding to the surveillance mechanism. Which of the following statement is incorrect?

#Unit 2. Cellular Organization

DNA damage leads to the activation of p21, a transcription factor that induces the expression of the gene encoding the CDK inhibitor p53.
When the DNA damage occurs during S phase or in G2, Cdc25C inhibition by Chk1/2 results in the inhibition of mitotic CDKs and hence arrest in G2.
Cells sense DNA replication stress that results in stalling or slowing of replication forks. Such stress triggers activation of the ATR-Chk1 checkpoint pathway and results in downregulation of S phase CDK activity and prevents the firing of late-replicating origins.
ATM halts cell cycle progression by Chk2-mediated inhibition of Cdc25, thus preventing activation of CDKs. This inhibition can occur in G1 or G2.

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#Question id: 6992

#Unit 5. Developmental Biology

Epimorphosis is regeneration through:

TLS Online TPP Program

#Question id: 25684

#Unit 5. Developmental Biology

Following statements were made regarding regeneration in different organisms:

A. The regenerating blastema cells in amphibians retain their specification even when they dedifferentiate.

B. A transgenic Hydra when made to misexpress B-catenin will show nun1erous ectopic tentacles.

C. In Planaria, if the Wnt pathway is activated, then the posterior blastema would regenerate a head.

D. A regenerating blastema is formd in the mammalian liver.

Which one of the following options represents all correct statement

TLS Online TPP Program

#Question id: 7286

#Unit 5. Developmental Biology

Which of the floral whorls is affected in apetala 3/pistillata (ap3/pi) mutants?

TLS Online TPP Program

#Question id: 7287

#Unit 5. Developmental Biology

Following statements are regarding to the the floral quartet model and the underlying ABCDE model of organ identity determination in Arabidopsis thaliana.

A. Five floral organ identities (sepals, petals, stamens, carpels, and ovules) are specified by the formation of floral organ-specific tetrameric complexes of MADS-domain transcription factors that bind to two nearby enhancer elements, forming a DNA loop in between.

B. A complex of two class A proteins (APETALA 1) and two class E proteins (SEPALLATA) determines petal identity.

C. A complex of one class A protein, one class E protein, and one of each of the class B proteins (APETALA 3 and PISTILLATA) determines sepal identity.

D. A complex of one class E protein, two class B proteins, and one class C protein (AGAMOUS) determines stamen identity, while a complex of two class E proteins and two class C proteins determines carpel identity.D. A complex of one class E protein, two class B proteins, and one class C protein (AGAMOUS) determines stamen identity, while a complex of two class E proteins and two class C proteins determines carpel identity.

E. A complex of one class E protein, one class C protein, and one of each of the class D proteins (SHATTERPROOF and SEEDSTICK) controls ovule identity.

Which of the following combination are correct?

TLS Online TPP Program

#Question id: 7288

#Unit 5. Developmental Biology

Following statements are regarding to the expression of genes in floral quartate model in Arabidopsis thaliana.

A. Sepals- AP1(heterodimer) + SEP(homodimer)

B. Petals-AP1(monomer)+PI(monomer)+AP3(monomer)+SEP(monomer)

C. Stamens- AP3(monomer)+PI(monomer)+AG(monomer)+SEP(monomer)

D. Carpels- AG(homodimer)+SEP(homodimer)

Which of the following genetic combinations are incorrect?

TLS Online TPP Program

#Question id: 7289

#Unit 5. Developmental Biology

The following scheme shows the flowering status of a plant species and the photoperiodism. Which of the following conclusions is most appropriate?