Bio Chem - Signal Transduction

Front 1

What are the difficulties in transducing a signal outside the cell into a cellular response inside the cell?

Back 1

the cells must be able to respond to the signal and molecules causing the signal generally need to be impermeable to the cell membrane.

Front 2

What are the two major classifications of signal transduction ?

Back 2

Membrane receptors, which cause an intracellular response. and Intracellular receptors that affect gene regulation.

Front 3

What is a ligand? What is the property of ligands that accounts for the two major classifications of signal transduction ?

Back 3

A ligand is an extracellular protein that is able to bind to a specific receptor. The property responsible for the two major classifications is the permeability of the ligand.

Front 4

Endocrine signaling molecules

Back 4

act on a distant tissue and move through the blood stream. i.e. insulin.

Front 5

Paracrine signaling molecules

Back 5

act on adjacent cells, i.e. histidine

Front 6

autocrine signaling molecules

Back 6

act on same cell. interleukin-2 and proliferation of T-cells.

Front 7

differences in histamine receptors

Back 7

H1 receptor is located in endothelium and smooth muscle and causes a vasodilation affect when acted upon by an antagonist. The H2 receptor is located in the stomach and causes a decrease in gastric acid secretion when acted upon by an antagonist.

Front 8

four enzymatic activities commonly found on receptors

Back 8

phosphorylation
dephosphorylation
cyclization
IP3 and DAG

Front 9

what does insulin receptor do?

Back 9

causes phosphorylation of the AA tyrosine.

Front 10

what are some of the downstream events in insulin signal transduction

Back 10

insulin causes glucose transporters to migrate towards cell surface