quiz 15 on cell signaling

Protein kinase A is activated by

binding of cAMP to its regulatory subunits.

The first step in growth factor pathway activation is

receptor dimerization

NO, nitric oxide, causes what reaction to occur?

increases in cGMP

The Ras protein is activated by

GTP binding

MAP kinase is an abbreviation for _______ protein kinase.

mitogen-activated

Which statement correctly describes how protein kinase A can activate genes?

Cytosolic protein kinase A is activated by cAMP to release the catalytic subunits, which move into the nucleus and phosphorylate general transcription factors.

A glucocorticoid binding to its receptor stimulates

formation of a receptor dimer that binds to and activates a gene.

Nitric oxide is a signal molecule that can

diffuse across cell membranes and directly alter the activity of intracellular enzymes.

Match the class of signaling that is occurring. autocrine

T cell stimulation

Match the class of signaling that is occurring. endocrine

growth hormone

Match the class of signaling that is occurring. cell-cell contact

plasmodesmata

Match the class of signaling that is occurring. paracrine

synaptic communication

Ras is a membrane-bound _______ when activated.

small monomeric G protein that binds GTP

What reaction does adenylyl cyclase catalyze?

the conversion of ATP to cAMP

Enkephalins and endorphins bind to the same receptors in the brain as

morphine

The GTP on the G protein that is linked to adenylyl cyclase is split to GDP and P_i

by the active a subunit.

The alpha subunit of the G protein that is associated with the epinephrine receptor, G_s,

activates adenylyl cyclase

 A trimeric G protein

has three subunits: alpha, beta and gamma

Hormones that signal through "second messengers" tend to be

hydrophilic signaling molecules

Which statement correctly describes how protein kinase A can activate genes?

Cytosolic protein kinase A is activated by cAMP to release the catalytic subunits, which move into the nucleus and phosphorylate general transcription factors.

Ras is a membrane-bound _______ when activated.

small monomeric G protein that binds GTP