In the case of the French flag model. we assume a source of morphogen at one end and a sink at the other and that the concentrations of morphogen at both ends are kept constant but are different from each other. If the cells can respond to threshold concentrations of the morphogen, Thresholds can represent the

a. amount of morphogen that must bind to receptors to activate an intracellular signaling system. 

b. concentrations of transcription factors required to activate particular genes.

c. concentration at any point effectively provides positional information.

d. amount of morphogen that must bind to receptors to inactivate an extracellular signaling system.

TLS Online TPP Program

#Question id: 18799

#Unit 13. Methods in Biology

Propidium iodide-labeled cells can be identify cells within the populations are at each stage of the cell cycle. After passing through flow cytometer a graph is observed

  

In this graph A, B, C, and D represent a cell stage which are

TLS Online TPP Program

#Question id: 18800

#Unit 13. Methods in Biology

Propidium iodide-labeled cells can be identify cells within the populations are at each stage of the cell cycle. After passing through flow cytometer a graph is observed

In this double diploid cell are found at 

TLS Online TPP Program

#Question id: 18801

#Unit 13. Methods in Biology

Instead of Propidium iodide-labeled cell an alternate compound can be used to which is

TLS Online TPP Program

#Question id: 18802

#Unit 13. Methods in Biology

Instead of Propidium iodide-labeled cell an alternate compound can be used which is Carboxyfluorescein succinimidyl ester (CFSE) in CFSE labeling amount of fluorescence emitted is cut in half each time the cell divides. The nature of this compound is

TLS Online TPP Program

#Question id: 18803

#Unit 13. Methods in Biology

Carboxyfluorescein succinimidyl ester (CFSE)is non-toxic to cells hence retained till many cycles in CFSE labeling amount of fluorescence emitted is cut in half each time the cell divides, after labelling the following graph is obtained 

 

In this graph 

TLS Online TPP Program

#Question id: 18804

#Unit 13. Methods in Biology

Non toxic labelling can be done by using