Practice Questions

TLS Online TPP Program

#Question id: 1251

Following statements are regarding to receptor serine kinases.

A. The two serines in each Smad3 that were phosphorylated by the RI receptor kinase bind to phosphoserine-binding sites in the MH1 domains of a Smad3 or a Smad4, forming a stable complex containing two molecules of phosphorylated Smad3 (or Smad2) and one molecule of the co-Smad (Smad4).

B. The bound importin then mediates translocation of the heteromeric R-Smad/co-Smad complex into the nucleus.

C. After importin dissociates inside the nucleus, the Smad3/Smad4 (or Smad2/Smad4) complex binds to other transcription factors to activate transcription of specific target genes.

D. Transcription of the PAI-1 gene requires formation of a complex of the transcription factor TFE3 with the R-Smad/co-Smad (Smad3/Smad4) complex and binding of all these proteins to specific sequences within the regulatory region of the PAI-1 gene.

E. Within the nucleus, R-Smads are further modified by phosphorylation of their linker domains, monoubiquitinylation of their MH1 domains, acetylation of their MH2 domains, and dephosphorylation of the C-terminal serines by nuclear phosphatases.

Which of the following combination is incorrect?

#Unit 4. Cell Communication and Cell Signaling

A, B and E
C and D
A and E
B only

More Questions

TLS Online TPP Program

#Question id: 15447

#Unit 4. Cell Communication and Cell Signaling

During development two types of B-cells will be formed:-

Some features about T1 and T2 cells given in below;

a) Maturity achieve

b) Found in blood circulation

c) Presence of Immunoglobulin IgM high and IgD low

d) Expressing CD21 and CD23

e) Cell expressing BAFF-R, Which bind with BAFF survival factor

Match the cell with their correct features;

TLS Online TPP Program

#Question id: 1389

#Unit 4. Cell Communication and Cell Signaling

Why has C. elegans proven to be a useful model for understanding apoptosis?

TLS Online TPP Program

#Question id: 1390

#Unit 4. Cell Communication and Cell Signaling

Which of the following statements describes the events of apoptosis?

TLS Online TPP Program

#Question id: 1391

#Unit 4. Cell Communication and Cell Signaling

If an adult person has a faulty version of the human analog to ced-4 of the nematode, which of the following is most likely to result?

TLS Online TPP Program

#Question id: 1392

#Unit 4. Cell Communication and Cell Signaling

In the nematode C. elegans, ced-9 prevents apoptosis in a normal cell in which of the following ways?

TLS Online TPP Program

#Question id: 1393

#Unit 4. Cell Communication and Cell Signaling

In research on aging (both cellular aging and organismal aging), it has been found that aged cells do not progress through the cell cycle as they had previously. Which of the following, if found in cells or organisms as they age, would provide evidence that this is related to cell signalling?