Social cells 1- cell to cell communication

what are ligands?

signalling molecules released by the cell to communicate

what does cell to cell communication effect?

growth

differentiation metabolisms

death

what are receptors?

receiving molecules capable of translating the extracellular signal into an intracellular modification

what are some short-distance communications?

autocrine signalling

paracrine signalling

contact-dependant/juxtacrine

what are some long distance communications?

synaptic

endocrine signalling

what are some characteristics of endocrine signalling?

tend to be lipophilic

very specific

very potent

may be produced by a gland

what are some characteristics of paracrine signalling?

exact distance not qualified

wide range of different ligands can start a paracrine signalling

the concentration of ligands is usually low and can be controlled in several ways

what are some characteristics of autocrine signalling?

the cell signalling to itself

it can decrease or promote signalling initiated by the cell itself

what are the 3 forms of juxtacrine/contact dependant signalling?

membrane proteins on each cell interact

membrane proteins interact with part of an extracellular matrix

junctions link cells allowing small molecules to pass between

how is an extracellular signal converted to an intracellular modification?

the ligand binds to a specific receptor on target cells

the receptor undergoes a conformational change once the ligand has bound

secondary messengers or enzymatic cascades amplify the signal

what are the 4 main types of receptors?

ion-channel couples

G-protein-coupled

enzyme-coupled

nuclear