Correct and appropriate signal transduction processes are generally under strong selective pressure and are determined by the properties of the molecules involved, the concentrations of signal and receptor molecules, and the binding affinities between signal and receptor. Therefore, a hormone action is very specific in a species at any one point in time. However, there are examples of very diverse functions of a specific hormone between groups of organisms. For example, thyroxin, which is produced in all vertebrates and many invertebrates, can trigger growth, differentiation, metamorphosis, maturation, reproduction, behavior, temperature tolerance, osmoregulation, or seasonal adaptation depending on the organism in which it is produced. What is the most logical explanation for such different responses triggered by thyroxin in organisms?

#Question id: 19703

#Unit 13. Methods in Biology

#Question id: 5164

#General Aptitude

When define a function f(N) = sum of digits of N , expressed as decimal number. E.g. F(137) = 1 + 3 + 7 = 11 : Evaluate f(2^7 3^5 5^6) .

#Question id: 18678

#Unit 13. Methods in Biology

#Question id: 1517

#Unit 4. Cell Communication and Cell Signaling

Following statements are regarding to cell death and its regulation.

A. In mammals, apoptosis can be triggered by oligomerization of Bax or Bak proteins in the outer mitochondrial membrane, leading to efflux of cytochrome c and SMAC/DIABLO proteins into the cytosol; these proteins then promote caspase activation and cell death.

B. Direct interactions between pro-apoptotic and anti-apoptotic proteins lead to cell death in the absence of trophic factors.

C. Direct interactions between pro-apoptotic and anti-apoptotic proteins lead to cell death in the presence of trophic factors.

D. Once activated, apoptotic proteases called caspases cleave specific intracellular substrates, leading to the demise of a cell.

Which of the following statements are correct?

#Question id: 2197

#Unit 2. Cellular Organization

 If a freshwater plant were put in sea water, its cells would: