Which of the following mutations would promote malignancy in cells whose proliferation is inhibited by TGFβ?

a. overexpression of Smad2               

b. loss of Smad 4

c. overexpression of TGFβ receptor I

d. loss of TGFβ receptor II

#Question id: 2986

#Unit 2. Cellular Organization

During ubiquitin-mediated protein degradation in various events of cell cycle, ubiquitin-protein ligases ubiquitinylate substrate proteins, marking them for degradation by proteasomes. Cyclins are degraded through the action of two different ubiquitin-protein ligases, SCF and the anaphase-promoting complex or cyclosome. Following statements are regarding to SCF and APC/C.

A. SCF controls the G1–S phase transition by degrading G1/S phase cyclins and, CDK inhibitory proteins.

B. APC/C degrades S phase and mitotic cyclins, thereby promoting the exit from mitosis.

C. SCF and APC/C are multi-subunit ubiquitin-protein ligases that belong to the RING finger family of ubiquitin protein ligases.

D. SCF and APC/C belong to the different ubiquitin-protein ligase family, their regulation is same.

E. SCF recognizes its substrates only when they are phosphorylated.

F. SCF and APC/C both recognizes its substrates only when they are phosphorylated.

Which of the following is incorrect?

#Question id: 33305

#Unit 1. Molecules and their Interaction Relevant to Biology

For the given equation, which representation is correct

#Question id: 5238

#Unit 5. Developmental Biology

all tissue types possess a unique stem cell niche, and despite many differences among the niche architecture of different tissues, several common principles of stem cell regulation can be applied to all environments. These principles involve extracellular mechanisms leading to intracellular changes that regulate stem cell behavior.

Match the following regulatory mechanism (column A) with the factors that regulate stem cell behavior (column B).

#Question id: 18614

#Unit 13. Methods in Biology

#Question id: 18376

#Unit 12. Applied Biology