Cell Signaling True or False?

Question

True or False?

All hydrophobic signaling molecules lead to slow responses

SOS activation of RAS is not an amplification step.

Inactivation of phosphatase activity turns on glycogen synthesis.

All second messengers are small hydrophilic molecules.

Answer 1

1:SOS is the key activator of the small GTPase Ras which is initiated by ,embrane recruitment of SOS via the adapter Grb-2 and balanced by rapid reversible Grb2:SOS binding kinetics.this is not an amplification process.

2: hydrophobic signalling molecules diffuse across the plasma membrane and interract with intracellular receptors or cytoplasmic receptors in short these hydrophobic cell signalling molecules lead to relatively slow responses

3:.since phophatase enymes are involved in dephosphorylation, its inactivation turns on glycogen synthesis.

4:the ability of small second messengers to leave the cell membrane and travel through the phosholipid bilayer makes them hydophilic.