Cell Signaling

Do we know what a signal transduction pathway is?

• Of Course

• Of course I do, but why don't you remind us for fun...

What is the important structural difference between estrogen and insulin

• estrogen is a peptide hormone, insulin is a steroid

• Estrogen is a glycogen hormone, insulin is a steroid

• Estrogen is a steroid hormone, insulin is a glycogen

• Estrogen is a steroid hormone, insulin is a peptide

Where are cell receptors found?

• Cell Surface

• Nuclear Surface and Cell Surface

• Everywhere inside the cell

• Extracellular matrix

What uses the delta signal protein and is responsible for transmembrane protein signaling between two cells?

• Neuronal

• Paracrine

• Juxtacrine

• None; there is no delta signal protein

Do you need 1 signal molecule to affect 1 molecule of change?

• Yes, signal transduction pathways are direct

• Yes, signals are inherently destroyed in affecting another molecule

• No, the signal molecule will bind to multiple different types of receptors in the cell to create multiple changes

• No, the signal transduction pathway includes signal amplification which proliferates the affect of the cell signal

What’s going on here?

• Ik

• idk

A G-protein is activated with acetylcholine: what happens next?

• GDP is released from alpha subunit and replaced for GTP

• GTP alpha subunit phosphorylates the beta subunit which can now do things

• The alpha subunit disassociates from the g protein and beta subunits, letting itself and the beta subunit do something

• the dephosphorylated alpha subunit rejoins the beta subunit and migrate back to the deactivated g protien

Out of the 3 types of cell surface receptors, which is a dimer in the activated state

• g-proteins

• Enzyme coupled receptors

• Ion Channels

An example of enzyme coupled receptors includes...

• creating the apoptosome

• inducing increased genomic expression of specified proteins by means of cAMP

• Releasing Ca2+ inside the cell

• Activating mitogen activated kinase kinase