If a stem cell divides symmetrically, have the ability to produce either two stem cells (increasing the stem cell pool by one) or two committed cells (decreasing the pool by one). This is called symmetrical renewing or symmetrical differentiating.

TLS Online TPP Program

#Id: 9032

#Unit 4. Cell Communication and Cell Signaling

TLS Online TPP Program

#Id: 9033

#Unit 4. Cell Communication and Cell Signaling

TLS Online TPP Program

#Id: 9034

#Unit 4. Cell Communication and Cell Signaling

Ligand binding depends on: 

Multiple weak, noncovalent forces

Molecular complementarity

TLS Online TPP Program

#Id: 9035

#Unit 4. Cell Communication and Cell Signaling

Binding of the ligand to the receptor causes the receptor to change from an inactive conformation (R) to an active conformation (R*). Only the active R* conformation of the receptor can trigger the signal transduction pathway.

TLS Online TPP Program

#Id: 9036

#Unit 4. Cell Communication and Cell Signaling

The affinity of a signal molecule’s binding to its receptor is quantified by the dissociation constant for binding (Kd).

TLS Online TPP Program

#Id: 9037

#Unit 4. Cell Communication and Cell Signaling

A plot of the amount of ligand bound to the receptor

[RL] versus the amount of free ligand [L] called a

ligand-binding or saturation curve