Cell Communication PT2

Question 1

what are G-protein linked receptors

Answer 1

Reacting with ligand. Functions like a switch, Either on or off. Gtp turns to gdp

Question 2

what are Second Messengers

Answer 2

Are small molecules or ions that relay signals received by cellsurface receptors to effector proteins
Examples:
cAMP, IP3

Question 3

structure and function of a

tyrosine-kinase receptor

Answer 3

Most abundant receptors
Ø They have enzymatic
activity
Ø They are tyrosine kinases
Ø Tyrosine kinases put
phosphates on
tyrosines
Ø Those phosphates come
from ATP
Ø Relay proteins bind to the
tyrosines

Question 4

what is Ligand-gated ion -channel receptor

Answer 4

Ligands flow in or out

When ligands leave the gate closes

Question 5

what is the Intercellular receptor

Answer 5

In cytosol or nucleus
Hormone goes into cell and binds w/ receptor
Examples of other steroid hormones are testosterone and estrogen

Question 6

The use of some of the same molecules in more than one pathway allows the cell to:

Answer 6

Economize on the number of different proteins it must make. Amplify the signal. Regulate the response at different points during the signaling