AP Biology

Cell Communication (Signaling)Part 2

Phosphorylation and Hydrolysis

Receptor Protein

G protein Receptor

Tyrosine – Kinase Receptor

Ion Channel ReceptorsSignalmolecule(ligand)

Gateclosed Ions

Ligand-gatedion channel receptor

Plasmamembrane

Gate closed

Gate open

Cellularresponse

Intracellular receptors

Secondary Messenger cAMP

ATP Cyclic AMP AMP

Adenylyl cyclase

PyrophosphateP P i

Phosphodiesterase

H2O

cAMP

ATPSecondmessenger

First messenger(signal moleculesuch as epinephrine)

G-protein-linkedreceptor

G protein

Adenylylcyclase

Proteinkinase A

Cellular responses

GTP

Secondary Messenger Calmodulin

CYTOSOL

Ca2+Endoplasmicreticulum (ER)

IP3-gatedcalcium channel

IP3 (secondmessenger)

DAG

PIP2G-protein-linkedreceptor Phospholipase C

G protein

Signal molecule(first messenger)

EXTRACELLULARFLUID

GTP

Ca2+ (secondmessenger)

Variousproteinsactivated

Cellularre-sponses

• • Question: All receptor proteins, regardless of

name, function or structure, operate the same way to trigger a response within a cell. In no more than three sentences, explain the signal transduction pathway. (5 Points)

•

• Scoring Rubric: 1pt. Discussion of reception and Confirmational shape change. Deduct half point for no mention of conformational shape change.

• 1pt. Discussion of transduction converting the signal in to a cellular process.

• 1pt. Discussion of the response occurring.• 1pt. Correct use of scientific terms.• 1pt. Answer has no more than three sentences.

(Following Directions.)• • This question addresses Essential Knowledge: 3.D.3