A) How does the ability of the ligand to cross the plasma membrane determine where the receptors for that ligand will be located? B) Compare the signaling transduction pathway of a hydrophobic ligand with that of a hydrophilic ligand. Solution The term ligand means a molecule bind to another molecule usually larger one.In cells a molecule binds to a receptor is called a ligand which alters the shape and ability of the receptor protein and a cascade of events are initiated results in cell signalling.Polar ligands(hydrophilic) are usually large and cannot cross the pasma membrane they usually binds to the protein receptors on the plasma membrane ,short half life and can be stored in vescles.Transported freely through blood plasma and rapid reponse whereas non polar ligands(hydrophobic) cross the membrane and binds to receptors in cytoplasm or nucleus.Half life is long ; cannot be stored so synthesize when needed.Need a carrier to transported through the blood.Response is very slow..

1. A) How does the ability of the ligand to cross the plasma membrane determine where the
receptors for that ligand will be located? B) Compare the signaling transduction pathway of a
hydrophobic ligand with that of a hydrophilic ligand.
Solution
The term ligand means a molecule bind to another molecule usually larger one.In cells a
molecule binds to a receptor is called a ligand which alters the shape and ability of the receptor
protein and a cascade of events are initiated results in cell signalling.Polar ligands(hydrophilic)
are usually large and cannot cross the pasma membrane they usually binds to the protein
receptors on the plasma membrane ,short half life and can be stored in vescles.Transported freely
through blood plasma and rapid reponse whereas non polar ligands(hydrophobic) cross the
membrane and binds to receptors in cytoplasm or nucleus.Half life is long ; cannot be stored so
synthesize when needed.Need a carrier to transported through the blood.Response is very slow.